1 /*
   2  * Stupid C parser, version 1e-6.
   3  *
   4  * Let's see how hard this is to do.
   5  *
   6  * Copyright (C) 2003 Transmeta Corp.
   7  *               2003-2004 Linus Torvalds
   8  * Copyright (C) 2004 Christopher Li
   9  *
  10  * Permission is hereby granted, free of charge, to any person obtaining a copy
  11  * of this software and associated documentation files (the "Software"), to deal
  12  * in the Software without restriction, including without limitation the rights
  13  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14  * copies of the Software, and to permit persons to whom the Software is
  15  * furnished to do so, subject to the following conditions:
  16  *
  17  * The above copyright notice and this permission notice shall be included in
  18  * all copies or substantial portions of the Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  23  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  25  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  26  * THE SOFTWARE.
  27  */
  28 
  29 #include <stdarg.h>
  30 #include <stdlib.h>
  31 #include <stdio.h>
  32 #include <string.h>
  33 #include <ctype.h>
  34 #include <unistd.h>
  35 #include <fcntl.h>
  36 #include <limits.h>
  37 
  38 #include "lib.h"
  39 #include "allocate.h"
  40 #include "token.h"
  41 #include "parse.h"
  42 #include "symbol.h"
  43 #include "scope.h"
  44 #include "expression.h"
  45 #include "target.h"
  46 
  47 static struct symbol_list **function_symbol_list;
  48 struct symbol_list *function_computed_target_list;
  49 struct statement_list *function_computed_goto_list;
  50 
  51 static struct token *statement(struct token *token, struct statement **tree);
  52 static struct token *handle_attributes(struct token *token, struct decl_state *ctx, unsigned int keywords);
  53 
  54 typedef struct token *declarator_t(struct token *, struct decl_state *);
  55 static declarator_t
  56         struct_specifier, union_specifier, enum_specifier,
  57         attribute_specifier, typeof_specifier, parse_asm_declarator,
  58         typedef_specifier, inline_specifier, auto_specifier,
  59         register_specifier, static_specifier, extern_specifier,
  60         thread_specifier, const_qualifier, volatile_qualifier;
  61 static declarator_t restrict_qualifier;
  62 static declarator_t atomic_qualifier;
  63 
  64 static struct token *parse_if_statement(struct token *token, struct statement *stmt);
  65 static struct token *parse_return_statement(struct token *token, struct statement *stmt);
  66 static struct token *parse_loop_iterator(struct token *token, struct statement *stmt);
  67 static struct token *parse_default_statement(struct token *token, struct statement *stmt);
  68 static struct token *parse_case_statement(struct token *token, struct statement *stmt);
  69 static struct token *parse_switch_statement(struct token *token, struct statement *stmt);
  70 static struct token *parse_for_statement(struct token *token, struct statement *stmt);
  71 static struct token *parse_while_statement(struct token *token, struct statement *stmt);
  72 static struct token *parse_do_statement(struct token *token, struct statement *stmt);
  73 static struct token *parse_goto_statement(struct token *token, struct statement *stmt);
  74 static struct token *parse_context_statement(struct token *token, struct statement *stmt);
  75 static struct token *parse_range_statement(struct token *token, struct statement *stmt);
  76 static struct token *parse_asm_statement(struct token *token, struct statement *stmt);
  77 static struct token *toplevel_asm_declaration(struct token *token, struct symbol_list **list);
  78 static struct token *parse_static_assert(struct token *token, struct symbol_list **unused);
  79 
  80 typedef struct token *attr_t(struct token *, struct symbol *,
  81                              struct decl_state *);
  82 
  83 static attr_t
  84         attribute_packed, attribute_aligned, attribute_modifier,
  85         attribute_ext_visible,
  86         attribute_bitwise,
  87         attribute_address_space, attribute_context,
  88         attribute_designated_init,
  89         attribute_transparent_union, ignore_attribute,
  90         attribute_mode, attribute_force;
  91 
  92 typedef struct symbol *to_mode_t(struct symbol *);
  93 
  94 static to_mode_t
  95         to_QI_mode, to_HI_mode, to_SI_mode, to_DI_mode, to_TI_mode;
  96 static to_mode_t to_pointer_mode, to_word_mode;
  97 
  98 enum {
  99         Set_T = 1,
 100         Set_S = 2,
 101         Set_Char = 4,
 102         Set_Int = 8,
 103         Set_Double = 16,
 104         Set_Float = 32,
 105         Set_Signed = 64,
 106         Set_Unsigned = 128,
 107         Set_Short = 256,
 108         Set_Long = 512,
 109         Set_Vlong = 1024,
 110         Set_Int128 = 2048,
 111         Set_Any = Set_T | Set_Short | Set_Long | Set_Signed | Set_Unsigned
 112 };
 113 
 114 enum {
 115         CInt = 0, CSInt, CUInt, CReal, CChar, CSChar, CUChar,
 116 };
 117 
 118 enum {
 119         SNone = 0, STypedef, SAuto, SRegister, SExtern, SStatic, SForced, SMax,
 120 };
 121 
 122 static void asm_modifier(struct token *token, unsigned long *mods, unsigned long mod)
 123 {
 124         if (*mods & mod)
 125                 warning(token->pos, "duplicated asm modifier");
 126         *mods |= mod;
 127 }
 128 
 129 static void asm_modifier_volatile(struct token *token, unsigned long *mods)
 130 {
 131         asm_modifier(token, mods, MOD_VOLATILE);
 132 }
 133 
 134 static void asm_modifier_inline(struct token *token, unsigned long *mods)
 135 {
 136         asm_modifier(token, mods, MOD_INLINE);
 137 }
 138 
 139 static struct symbol_op typedef_op = {
 140         .type = KW_MODIFIER,
 141         .declarator = typedef_specifier,
 142 };
 143 
 144 static struct symbol_op inline_op = {
 145         .type = KW_MODIFIER,
 146         .declarator = inline_specifier,
 147         .asm_modifier = asm_modifier_inline,
 148 };
 149 
 150 static declarator_t noreturn_specifier;
 151 static struct symbol_op noreturn_op = {
 152         .type = KW_MODIFIER,
 153         .declarator = noreturn_specifier,
 154 };
 155 
 156 static declarator_t alignas_specifier;
 157 static struct symbol_op alignas_op = {
 158         .type = KW_MODIFIER,
 159         .declarator = alignas_specifier,
 160 };
 161 
 162 static struct symbol_op auto_op = {
 163         .type = KW_MODIFIER,
 164         .declarator = auto_specifier,
 165 };
 166 
 167 static struct symbol_op register_op = {
 168         .type = KW_MODIFIER,
 169         .declarator = register_specifier,
 170 };
 171 
 172 static struct symbol_op static_op = {
 173         .type = KW_MODIFIER,
 174         .declarator = static_specifier,
 175 };
 176 
 177 static struct symbol_op extern_op = {
 178         .type = KW_MODIFIER,
 179         .declarator = extern_specifier,
 180 };
 181 
 182 static struct symbol_op thread_op = {
 183         .type = KW_MODIFIER,
 184         .declarator = thread_specifier,
 185 };
 186 
 187 static struct symbol_op const_op = {
 188         .type = KW_QUALIFIER,
 189         .declarator = const_qualifier,
 190 };
 191 
 192 static struct symbol_op volatile_op = {
 193         .type = KW_QUALIFIER,
 194         .declarator = volatile_qualifier,
 195         .asm_modifier = asm_modifier_volatile,
 196 };
 197 
 198 static struct symbol_op restrict_op = {
 199         .type = KW_QUALIFIER,
 200         .declarator = restrict_qualifier,
 201 };
 202 
 203 static struct symbol_op atomic_op = {
 204         .type = KW_QUALIFIER,
 205         .declarator = atomic_qualifier,
 206 };
 207 
 208 static struct symbol_op typeof_op = {
 209         .type = KW_SPECIFIER,
 210         .declarator = typeof_specifier,
 211         .test = Set_Any,
 212         .set = Set_S|Set_T,
 213 };
 214 
 215 static struct symbol_op attribute_op = {
 216         .type = KW_ATTRIBUTE,
 217         .declarator = attribute_specifier,
 218 };
 219 
 220 static struct symbol_op struct_op = {
 221         .type = KW_SPECIFIER,
 222         .declarator = struct_specifier,
 223         .test = Set_Any,
 224         .set = Set_S|Set_T,
 225 };
 226 
 227 static struct symbol_op union_op = {
 228         .type = KW_SPECIFIER,
 229         .declarator = union_specifier,
 230         .test = Set_Any,
 231         .set = Set_S|Set_T,
 232 };
 233 
 234 static struct symbol_op enum_op = {
 235         .type = KW_SPECIFIER,
 236         .declarator = enum_specifier,
 237         .test = Set_Any,
 238         .set = Set_S|Set_T,
 239 };
 240 
 241 static struct symbol_op spec_op = {
 242         .type = KW_SPECIFIER | KW_EXACT,
 243         .test = Set_Any,
 244         .set = Set_S|Set_T,
 245 };
 246 
 247 static struct symbol_op char_op = {
 248         .type = KW_SPECIFIER,
 249         .test = Set_T|Set_Long|Set_Short,
 250         .set = Set_T|Set_Char,
 251         .class = CChar,
 252 };
 253 
 254 static struct symbol_op int_op = {
 255         .type = KW_SPECIFIER,
 256         .test = Set_T,
 257         .set = Set_T|Set_Int,
 258 };
 259 
 260 static struct symbol_op double_op = {
 261         .type = KW_SPECIFIER,
 262         .test = Set_T|Set_Signed|Set_Unsigned|Set_Short|Set_Vlong,
 263         .set = Set_T|Set_Double,
 264         .class = CReal,
 265 };
 266 
 267 static struct symbol_op float_op = {
 268         .type = KW_SPECIFIER | KW_SHORT,
 269         .test = Set_T|Set_Signed|Set_Unsigned|Set_Short|Set_Long,
 270         .set = Set_T|Set_Float,
 271         .class = CReal,
 272 };
 273 
 274 static struct symbol_op short_op = {
 275         .type = KW_SPECIFIER | KW_SHORT,
 276         .test = Set_S|Set_Char|Set_Float|Set_Double|Set_Long|Set_Short,
 277         .set = Set_Short,
 278 };
 279 
 280 static struct symbol_op signed_op = {
 281         .type = KW_SPECIFIER,
 282         .test = Set_S|Set_Float|Set_Double|Set_Signed|Set_Unsigned,
 283         .set = Set_Signed,
 284         .class = CSInt,
 285 };
 286 
 287 static struct symbol_op unsigned_op = {
 288         .type = KW_SPECIFIER,
 289         .test = Set_S|Set_Float|Set_Double|Set_Signed|Set_Unsigned,
 290         .set = Set_Unsigned,
 291         .class = CUInt,
 292 };
 293 
 294 static struct symbol_op long_op = {
 295         .type = KW_SPECIFIER | KW_LONG,
 296         .test = Set_S|Set_Char|Set_Float|Set_Short|Set_Vlong,
 297         .set = Set_Long,
 298 };
 299 
 300 static struct symbol_op int128_op = {
 301         .type = KW_SPECIFIER | KW_LONG,
 302         .test = Set_S|Set_T|Set_Char|Set_Short|Set_Int|Set_Float|Set_Double|Set_Long|Set_Vlong|Set_Int128,
 303         .set =  Set_T|Set_Int128,
 304 };
 305 
 306 static struct symbol_op if_op = {
 307         .statement = parse_if_statement,
 308 };
 309 
 310 static struct symbol_op return_op = {
 311         .statement = parse_return_statement,
 312 };
 313 
 314 static struct symbol_op loop_iter_op = {
 315         .statement = parse_loop_iterator,
 316 };
 317 
 318 static struct symbol_op default_op = {
 319         .statement = parse_default_statement,
 320 };
 321 
 322 static struct symbol_op case_op = {
 323         .statement = parse_case_statement,
 324 };
 325 
 326 static struct symbol_op switch_op = {
 327         .statement = parse_switch_statement,
 328 };
 329 
 330 static struct symbol_op for_op = {
 331         .statement = parse_for_statement,
 332 };
 333 
 334 static struct symbol_op while_op = {
 335         .statement = parse_while_statement,
 336 };
 337 
 338 static struct symbol_op do_op = {
 339         .statement = parse_do_statement,
 340 };
 341 
 342 static struct symbol_op goto_op = {
 343         .statement = parse_goto_statement,
 344 };
 345 
 346 static struct symbol_op __context___op = {
 347         .statement = parse_context_statement,
 348 };
 349 
 350 static struct symbol_op range_op = {
 351         .statement = parse_range_statement,
 352 };
 353 
 354 static struct symbol_op asm_op = {
 355         .type = KW_ASM,
 356         .declarator = parse_asm_declarator,
 357         .statement = parse_asm_statement,
 358         .toplevel = toplevel_asm_declaration,
 359 };
 360 
 361 static struct symbol_op static_assert_op = {
 362         .toplevel = parse_static_assert,
 363 };
 364 
 365 static struct symbol_op packed_op = {
 366         .attribute = attribute_packed,
 367 };
 368 
 369 static struct symbol_op aligned_op = {
 370         .attribute = attribute_aligned,
 371 };
 372 
 373 static struct symbol_op attr_mod_op = {
 374         .attribute = attribute_modifier,
 375 };
 376 
 377 static struct symbol_op ext_visible_op = {
 378         .attribute = attribute_ext_visible,
 379 };
 380 
 381 static struct symbol_op attr_bitwise_op = {
 382         .attribute = attribute_bitwise,
 383 };
 384 
 385 static struct symbol_op attr_force_op = {
 386         .attribute = attribute_force,
 387 };
 388 
 389 static struct symbol_op address_space_op = {
 390         .attribute = attribute_address_space,
 391 };
 392 
 393 static struct symbol_op mode_op = {
 394         .attribute = attribute_mode,
 395 };
 396 
 397 static struct symbol_op context_op = {
 398         .attribute = attribute_context,
 399 };
 400 
 401 static struct symbol_op designated_init_op = {
 402         .attribute = attribute_designated_init,
 403 };
 404 
 405 static struct symbol_op transparent_union_op = {
 406         .attribute = attribute_transparent_union,
 407 };
 408 
 409 static struct symbol_op ignore_attr_op = {
 410         .attribute = ignore_attribute,
 411 };
 412 
 413 static struct symbol_op mode_QI_op = {
 414         .type = KW_MODE,
 415         .to_mode = to_QI_mode
 416 };
 417 
 418 static struct symbol_op mode_HI_op = {
 419         .type = KW_MODE,
 420         .to_mode = to_HI_mode
 421 };
 422 
 423 static struct symbol_op mode_SI_op = {
 424         .type = KW_MODE,
 425         .to_mode = to_SI_mode
 426 };
 427 
 428 static struct symbol_op mode_DI_op = {
 429         .type = KW_MODE,
 430         .to_mode = to_DI_mode
 431 };
 432 
 433 static struct symbol_op mode_TI_op = {
 434         .type = KW_MODE,
 435         .to_mode = to_TI_mode
 436 };
 437 
 438 static struct symbol_op mode_pointer_op = {
 439         .type = KW_MODE,
 440         .to_mode = to_pointer_mode
 441 };
 442 
 443 static struct symbol_op mode_word_op = {
 444         .type = KW_MODE,
 445         .to_mode = to_word_mode
 446 };
 447 
 448 /* Using NS_TYPEDEF will also make the keyword a reserved one */
 449 static struct init_keyword {
 450         const char *name;
 451         enum namespace ns;
 452         unsigned long modifiers;
 453         struct symbol_op *op;
 454         struct symbol *type;
 455 } keyword_table[] = {
 456         /* Type qualifiers */
 457         { "const",      NS_TYPEDEF, .op = &const_op },
 458         { "__const",    NS_TYPEDEF, .op = &const_op },
 459         { "__const__",  NS_TYPEDEF, .op = &const_op },
 460         { "volatile",   NS_TYPEDEF, .op = &volatile_op },
 461         { "__volatile",         NS_TYPEDEF, .op = &volatile_op },
 462         { "__volatile__",       NS_TYPEDEF, .op = &volatile_op },
 463         { "restrict",   NS_TYPEDEF, .op = &restrict_op},
 464         { "__restrict", NS_TYPEDEF, .op = &restrict_op},
 465         { "__restrict__",       NS_TYPEDEF, .op = &restrict_op},
 466         { "_Atomic",    NS_TYPEDEF, .op = &atomic_op},
 467 
 468         /* Typedef.. */
 469         { "typedef",    NS_TYPEDEF, .op = &typedef_op },
 470 
 471         /* Type specifiers */
 472         { "void",       NS_TYPEDEF, .type = &void_ctype, .op = &spec_op},
 473         { "char",       NS_TYPEDEF, .op = &char_op },
 474         { "short",      NS_TYPEDEF, .op = &short_op },
 475         { "int",        NS_TYPEDEF, .op = &int_op },
 476         { "long",       NS_TYPEDEF, .op = &long_op },
 477         { "float",      NS_TYPEDEF, .op = &float_op },
 478         { "double",     NS_TYPEDEF, .op = &double_op },
 479         { "signed",     NS_TYPEDEF, .op = &signed_op },
 480         { "__signed",   NS_TYPEDEF, .op = &signed_op },
 481         { "__signed__", NS_TYPEDEF, .op = &signed_op },
 482         { "unsigned",   NS_TYPEDEF, .op = &unsigned_op },
 483         { "__int128",   NS_TYPEDEF, .op = &int128_op },
 484         { "_Bool",      NS_TYPEDEF, .type = &bool_ctype, .op = &spec_op },
 485 
 486         /* Predeclared types */
 487         { "__builtin_va_list", NS_TYPEDEF, .type = &ptr_ctype, .op = &spec_op },
 488         { "__builtin_ms_va_list", NS_TYPEDEF, .type = &ptr_ctype, .op = &spec_op },
 489         { "__int128_t", NS_TYPEDEF, .type = &lllong_ctype, .op = &spec_op },
 490         { "__uint128_t",NS_TYPEDEF, .type = &ulllong_ctype, .op = &spec_op },
 491         { "_Float32",   NS_TYPEDEF, .type = &float32_ctype, .op = &spec_op },
 492         { "_Float32x",  NS_TYPEDEF, .type = &float32x_ctype, .op = &spec_op },
 493         { "_Float64",   NS_TYPEDEF, .type = &float64_ctype, .op = &spec_op },
 494         { "_Float64x",  NS_TYPEDEF, .type = &float64x_ctype, .op = &spec_op },
 495         { "_Float128",  NS_TYPEDEF, .type = &float128_ctype, .op = &spec_op },
 496 
 497         /* Extended types */
 498         { "typeof",     NS_TYPEDEF, .op = &typeof_op },
 499         { "__typeof",   NS_TYPEDEF, .op = &typeof_op },
 500         { "__typeof__", NS_TYPEDEF, .op = &typeof_op },
 501 
 502         { "__attribute",   NS_TYPEDEF, .op = &attribute_op },
 503         { "__attribute__", NS_TYPEDEF, .op = &attribute_op },
 504 
 505         { "struct",     NS_TYPEDEF, .op = &struct_op },
 506         { "union",      NS_TYPEDEF, .op = &union_op },
 507         { "enum",       NS_TYPEDEF, .op = &enum_op },
 508 
 509         { "inline",     NS_TYPEDEF, .op = &inline_op },
 510         { "__inline",   NS_TYPEDEF, .op = &inline_op },
 511         { "__inline__", NS_TYPEDEF, .op = &inline_op },
 512 
 513         { "_Noreturn",  NS_TYPEDEF, .op = &noreturn_op },
 514 
 515         { "_Alignas",   NS_TYPEDEF, .op = &alignas_op },
 516 
 517         /* Static assertion */
 518         { "_Static_assert", NS_KEYWORD, .op = &static_assert_op },
 519 
 520         /* Storage class */
 521         { "auto",       NS_TYPEDEF, .op = &auto_op },
 522         { "register",   NS_TYPEDEF, .op = &register_op },
 523         { "static",     NS_TYPEDEF, .op = &static_op },
 524         { "extern",     NS_TYPEDEF, .op = &extern_op },
 525         { "__thread",   NS_TYPEDEF, .op = &thread_op },
 526         { "_Thread_local",      NS_TYPEDEF, .op = &thread_op },
 527 
 528         /* Statement */
 529         { "if",         NS_KEYWORD, .op = &if_op },
 530         { "return",     NS_KEYWORD, .op = &return_op },
 531         { "break",      NS_KEYWORD, .op = &loop_iter_op },
 532         { "continue",   NS_KEYWORD, .op = &loop_iter_op },
 533         { "default",    NS_KEYWORD, .op = &default_op },
 534         { "case",       NS_KEYWORD, .op = &case_op },
 535         { "switch",     NS_KEYWORD, .op = &switch_op },
 536         { "for",        NS_KEYWORD, .op = &for_op },
 537         { "while",      NS_KEYWORD, .op = &while_op },
 538         { "do",         NS_KEYWORD, .op = &do_op },
 539         { "goto",       NS_KEYWORD, .op = &goto_op },
 540         { "__context__",NS_KEYWORD, .op = &__context___op },
 541         { "__range__",  NS_KEYWORD, .op = &range_op },
 542         { "asm",        NS_KEYWORD, .op = &asm_op },
 543         { "__asm",      NS_KEYWORD, .op = &asm_op },
 544         { "__asm__",    NS_KEYWORD, .op = &asm_op },
 545 
 546         /* Attribute */
 547         { "packed",     NS_KEYWORD, .op = &packed_op },
 548         { "__packed__", NS_KEYWORD, .op = &packed_op },
 549         { "aligned",    NS_KEYWORD, .op = &aligned_op },
 550         { "__aligned__",NS_KEYWORD, .op = &aligned_op },
 551         { "nocast",     NS_KEYWORD,     MOD_NOCAST,     .op = &attr_mod_op },
 552         { "noderef",    NS_KEYWORD,     MOD_NODEREF,    .op = &attr_mod_op },
 553         { "safe",       NS_KEYWORD,     MOD_SAFE,       .op = &attr_mod_op },
 554         { "force",      NS_KEYWORD,     .op = &attr_force_op },
 555         { "bitwise",    NS_KEYWORD,     MOD_BITWISE,    .op = &attr_bitwise_op },
 556         { "__bitwise__",NS_KEYWORD,     MOD_BITWISE,    .op = &attr_bitwise_op },
 557         { "address_space",NS_KEYWORD,   .op = &address_space_op },
 558         { "context",    NS_KEYWORD,     .op = &context_op },
 559         { "designated_init",    NS_KEYWORD,     .op = &designated_init_op },
 560         { "__designated_init__",        NS_KEYWORD,     .op = &designated_init_op },
 561         { "transparent_union",  NS_KEYWORD,     .op = &transparent_union_op },
 562         { "__transparent_union__",      NS_KEYWORD,     .op = &transparent_union_op },
 563         { "noreturn",   NS_KEYWORD,     MOD_NORETURN,   .op = &attr_mod_op },
 564         { "__noreturn__",       NS_KEYWORD,     MOD_NORETURN,   .op = &attr_mod_op },
 565         { "pure",       NS_KEYWORD,     MOD_PURE,       .op = &attr_mod_op },
 566         {"__pure__",    NS_KEYWORD,     MOD_PURE,       .op = &attr_mod_op },
 567         {"const",       NS_KEYWORD,     MOD_PURE,       .op = &attr_mod_op },
 568         {"__const",     NS_KEYWORD,     MOD_PURE,       .op = &attr_mod_op },
 569         {"__const__",   NS_KEYWORD,     MOD_PURE,       .op = &attr_mod_op },
 570         {"externally_visible",  NS_KEYWORD,     .op = &ext_visible_op },
 571         {"__externally_visible__",      NS_KEYWORD,     .op = &ext_visible_op },
 572 
 573         { "mode",       NS_KEYWORD,     .op = &mode_op },
 574         { "__mode__",   NS_KEYWORD,     .op = &mode_op },
 575         { "QI",         NS_KEYWORD,     .op = &mode_QI_op },
 576         { "__QI__",     NS_KEYWORD,     .op = &mode_QI_op },
 577         { "HI",         NS_KEYWORD,     .op = &mode_HI_op },
 578         { "__HI__",     NS_KEYWORD,     .op = &mode_HI_op },
 579         { "SI",         NS_KEYWORD,     .op = &mode_SI_op },
 580         { "__SI__",     NS_KEYWORD,     .op = &mode_SI_op },
 581         { "DI",         NS_KEYWORD,     .op = &mode_DI_op },
 582         { "__DI__",     NS_KEYWORD,     .op = &mode_DI_op },
 583         { "TI",         NS_KEYWORD,     .op = &mode_TI_op },
 584         { "__TI__",     NS_KEYWORD,     .op = &mode_TI_op },
 585         { "byte",       NS_KEYWORD,     .op = &mode_QI_op },
 586         { "__byte__",   NS_KEYWORD,     .op = &mode_QI_op },
 587         { "pointer",    NS_KEYWORD,     .op = &mode_pointer_op },
 588         { "__pointer__",NS_KEYWORD,     .op = &mode_pointer_op },
 589         { "word",       NS_KEYWORD,     .op = &mode_word_op },
 590         { "__word__",   NS_KEYWORD,     .op = &mode_word_op },
 591 };
 592 
 593 
 594 static const char *ignored_attributes[] = {
 595 
 596 #define GCC_ATTR(x)             \
 597         STRINGIFY(x),           \
 598         STRINGIFY(__##x##__),
 599 
 600 #include "gcc-attr-list.h"
 601 
 602 #undef GCC_ATTR
 603 
 604         "bounded",
 605         "__bounded__",
 606         "__noclone",
 607         "__nonnull",
 608         "__nothrow",
 609 };
 610 
 611 
 612 void init_parser(int stream)
 613 {
 614         int i;
 615         for (i = 0; i < ARRAY_SIZE(keyword_table); i++) {
 616                 struct init_keyword *ptr = keyword_table + i;
 617                 struct symbol *sym = create_symbol(stream, ptr->name, SYM_KEYWORD, ptr->ns);
 618                 sym->ident->keyword = 1;
 619                 if (ptr->ns == NS_TYPEDEF)
 620                         sym->ident->reserved = 1;
 621                 sym->ctype.modifiers = ptr->modifiers;
 622                 sym->ctype.base_type = ptr->type;
 623                 sym->op = ptr->op;
 624         }
 625 
 626         for (i = 0; i < ARRAY_SIZE(ignored_attributes); i++) {
 627                 const char * name = ignored_attributes[i];
 628                 struct symbol *sym = create_symbol(stream, name, SYM_KEYWORD,
 629                                                    NS_KEYWORD);
 630                 if (!sym->op) {
 631                         sym->ident->keyword = 1;
 632                         sym->op = &ignore_attr_op;
 633                 }
 634         }
 635 }
 636 
 637 
 638 // Add a symbol to the list of function-local symbols
 639 static void fn_local_symbol(struct symbol *sym)
 640 {
 641         if (function_symbol_list)
 642                 add_symbol(function_symbol_list, sym);
 643 }
 644 
 645 static int SENTINEL_ATTR match_idents(struct token *token, ...)
 646 {
 647         va_list args;
 648         struct ident * next;
 649 
 650         if (token_type(token) != TOKEN_IDENT)
 651                 return 0;
 652 
 653         va_start(args, token);
 654         do {
 655                 next = va_arg(args, struct ident *);
 656         } while (next && token->ident != next);
 657         va_end(args);
 658 
 659         return next && token->ident == next;
 660 }
 661 
 662 
 663 struct statement *alloc_statement(struct position pos, int type)
 664 {
 665         struct statement *stmt = __alloc_statement(0);
 666         stmt->type = type;
 667         stmt->pos = pos;
 668         return stmt;
 669 }
 670 
 671 static struct token *struct_declaration_list(struct token *token, struct symbol_list **list);
 672 
 673 static void apply_ctype(struct position pos, struct ctype *thistype, struct ctype *ctype);
 674 
 675 static void apply_modifiers(struct position pos, struct decl_state *ctx)
 676 {
 677         struct symbol *ctype;
 678         if (!ctx->mode)
 679                 return;
 680         ctype = ctx->mode->to_mode(ctx->ctype.base_type);
 681         if (!ctype)
 682                 sparse_error(pos, "don't know how to apply mode to %s",
 683                                 show_typename(ctx->ctype.base_type));
 684         else
 685                 ctx->ctype.base_type = ctype;
 686         
 687 }
 688 
 689 static struct symbol * alloc_indirect_symbol(struct position pos, struct ctype *ctype, int type)
 690 {
 691         struct symbol *sym = alloc_symbol(pos, type);
 692 
 693         sym->ctype.base_type = ctype->base_type;
 694         sym->ctype.modifiers = ctype->modifiers;
 695 
 696         ctype->base_type = sym;
 697         ctype->modifiers = 0;
 698         return sym;
 699 }
 700 
 701 /*
 702  * NOTE! NS_LABEL is not just a different namespace,
 703  * it also ends up using function scope instead of the
 704  * regular symbol scope.
 705  */
 706 struct symbol *label_symbol(struct token *token)
 707 {
 708         struct symbol *sym = lookup_symbol(token->ident, NS_LABEL);
 709         if (!sym) {
 710                 sym = alloc_symbol(token->pos, SYM_LABEL);
 711                 bind_symbol(sym, token->ident, NS_LABEL);
 712                 fn_local_symbol(sym);
 713         }
 714         return sym;
 715 }
 716 
 717 static struct token *struct_union_enum_specifier(enum type type,
 718         struct token *token, struct decl_state *ctx,
 719         struct token *(*parse)(struct token *, struct symbol *))
 720 {
 721         struct symbol *sym;
 722         struct position *repos;
 723 
 724         token = handle_attributes(token, ctx, KW_ATTRIBUTE);
 725         if (token_type(token) == TOKEN_IDENT) {
 726                 sym = lookup_symbol(token->ident, NS_STRUCT);
 727                 if (!sym ||
 728                     (is_outer_scope(sym->scope) &&
 729                      (match_op(token->next,';') || match_op(token->next,'{')))) {
 730                         // Either a new symbol, or else an out-of-scope
 731                         // symbol being redefined.
 732                         sym = alloc_symbol(token->pos, type);
 733                         bind_symbol(sym, token->ident, NS_STRUCT);
 734                 }
 735                 if (sym->type != type)
 736                         error_die(token->pos, "invalid tag applied to %s", show_typename (sym));
 737                 ctx->ctype.base_type = sym;
 738                 repos = &token->pos;
 739                 token = token->next;
 740                 if (match_op(token, '{')) {
 741                         struct decl_state attr = { .ctype.base_type = sym, };
 742 
 743                         // The following test is actually wrong for empty
 744                         // structs, but (1) they are not C99, (2) gcc does
 745                         // the same thing, and (3) it's easier.
 746                         if (sym->symbol_list)
 747                                 error_die(token->pos, "redefinition of %s", show_typename (sym));
 748                         sym->pos = *repos;
 749                         token = parse(token->next, sym);
 750                         token = expect(token, '}', "at end of struct-union-enum-specifier");
 751 
 752                         token = handle_attributes(token, &attr, KW_ATTRIBUTE);
 753                         apply_ctype(token->pos, &attr.ctype, &sym->ctype);
 754 
 755                         // Mark the structure as needing re-examination
 756                         sym->examined = 0;
 757                         sym->endpos = token->pos;
 758                 }
 759                 return token;
 760         }
 761 
 762         // private struct/union/enum type
 763         if (!match_op(token, '{')) {
 764                 sparse_error(token->pos, "expected declaration");
 765                 ctx->ctype.base_type = &bad_ctype;
 766                 return token;
 767         }
 768 
 769         sym = alloc_symbol(token->pos, type);
 770         token = parse(token->next, sym);
 771         ctx->ctype.base_type = sym;
 772         token =  expect(token, '}', "at end of specifier");
 773         sym->endpos = token->pos;
 774 
 775         return token;
 776 }
 777 
 778 static struct token *parse_struct_declaration(struct token *token, struct symbol *sym)
 779 {
 780         struct symbol *field, *last = NULL;
 781         struct token *res;
 782         res = struct_declaration_list(token, &sym->symbol_list);
 783         FOR_EACH_PTR(sym->symbol_list, field) {
 784                 if (!field->ident) {
 785                         struct symbol *base = field->ctype.base_type;
 786                         if (base && base->type == SYM_BITFIELD)
 787                                 continue;
 788                 }
 789                 if (last)
 790                         last->next_subobject = field;
 791                 last = field;
 792         } END_FOR_EACH_PTR(field);
 793         return res;
 794 }
 795 
 796 static struct token *parse_union_declaration(struct token *token, struct symbol *sym)
 797 {
 798         return struct_declaration_list(token, &sym->symbol_list);
 799 }
 800 
 801 static struct token *struct_specifier(struct token *token, struct decl_state *ctx)
 802 {
 803         return struct_union_enum_specifier(SYM_STRUCT, token, ctx, parse_struct_declaration);
 804 }
 805 
 806 static struct token *union_specifier(struct token *token, struct decl_state *ctx)
 807 {
 808         return struct_union_enum_specifier(SYM_UNION, token, ctx, parse_union_declaration);
 809 }
 810 
 811 ///
 812 // safe right shift
 813 //
 814 // This allow to use a shift amount as big (or bigger)
 815 // than the width of the value to be shifted, in which case
 816 // the result is, of course, 0.
 817 static unsigned long long rshift(unsigned long long val, unsigned int n)
 818 {
 819         if (n >= (sizeof(val) * 8))
 820                 return 0;
 821         return val >> n;
 822 }
 823 
 824 struct range {
 825         long long               neg;
 826         unsigned long long      pos;
 827 };
 828 
 829 static void update_range(struct range *range, unsigned long long uval, struct symbol *vtype)
 830 {
 831         long long sval = uval;
 832 
 833         if (is_signed_type(vtype) && (sval < 0)) {
 834                 if (sval < range->neg)
 835                         range->neg = sval;
 836         } else {
 837                 if (uval > range->pos)
 838                         range->pos = uval;
 839         }
 840 }
 841 
 842 static int type_is_ok(struct symbol *type, struct range range)
 843 {
 844         int shift = type->bit_size;
 845         int is_unsigned = type->ctype.modifiers & MOD_UNSIGNED;
 846 
 847         if (!is_unsigned)
 848                 shift--;
 849         if (rshift(range.pos, shift))
 850                 return 0;
 851         if (range.neg == 0)
 852                 return 1;
 853         if (is_unsigned)
 854                 return 0;
 855         if (rshift(~range.neg, shift))
 856                 return 0;
 857         return 1;
 858 }
 859 
 860 static struct range type_range(struct symbol *type)
 861 {
 862         struct range range;
 863         unsigned int size = type->bit_size;
 864         unsigned long long max;
 865         long long min;
 866 
 867         if (is_signed_type(type)) {
 868                 min = sign_bit(size);
 869                 max = min - 1;
 870         } else {
 871                 min = 0;
 872                 max = bits_mask(size);
 873         }
 874 
 875         range.pos = max;
 876         range.neg = min;
 877         return range;
 878 }
 879 
 880 static int val_in_range(struct range *range, long long sval, struct symbol *vtype)
 881 {
 882         unsigned long long uval = sval;
 883 
 884         if (is_signed_type(vtype) && (sval < 0))
 885                 return range->neg <= sval;
 886         else
 887                 return uval <= range->pos;
 888 }
 889 
 890 static void cast_enum_list(struct symbol_list *list, struct symbol *base_type)
 891 {
 892         struct range irange = type_range(&int_ctype);
 893         struct symbol *sym;
 894 
 895         FOR_EACH_PTR(list, sym) {
 896                 struct expression *expr = sym->initializer;
 897                 struct symbol *ctype;
 898                 long long val;
 899                 if (expr->type != EXPR_VALUE)
 900                         continue;
 901                 ctype = expr->ctype;
 902                 val = get_expression_value(expr);
 903                 if (is_int_type(ctype) && val_in_range(&irange, val, ctype)) {
 904                         expr->ctype = &int_ctype;
 905                         continue;
 906                 }
 907                 if (ctype->bit_size == base_type->bit_size) {
 908                         expr->ctype = base_type;
 909                         continue;
 910                 }
 911                 cast_value(expr, base_type, expr, ctype);
 912                 expr->ctype = base_type;
 913         } END_FOR_EACH_PTR(sym);
 914 }
 915 
 916 static struct token *parse_enum_declaration(struct token *token, struct symbol *parent)
 917 {
 918         unsigned long long lastval = 0;
 919         struct symbol *ctype = NULL, *base_type = NULL;
 920         struct range range = { };
 921         int mix_bitwise = 0;
 922 
 923         parent->examined = 1;
 924         parent->ctype.base_type = &int_ctype;
 925         while (token_type(token) == TOKEN_IDENT) {
 926                 struct expression *expr = NULL;
 927                 struct token *next = token->next;
 928                 struct symbol *sym;
 929 
 930                 if (match_op(next, '=')) {
 931                         next = constant_expression(next->next, &expr);
 932                         lastval = get_expression_value(expr);
 933                         ctype = &void_ctype;
 934                         if (expr && expr->ctype)
 935                                 ctype = expr->ctype;
 936                 } else if (!ctype) {
 937                         ctype = &int_ctype;
 938                 } else if (is_int_type(ctype)) {
 939                         lastval++;
 940                 } else {
 941                         error_die(token->pos, "can't increment the last enum member");
 942                 }
 943 
 944                 if (!expr) {
 945                         expr = alloc_expression(token->pos, EXPR_VALUE);
 946                         expr->value = lastval;
 947                         expr->ctype = ctype;
 948                 }
 949 
 950                 sym = alloc_symbol(token->pos, SYM_NODE);
 951                 bind_symbol(sym, token->ident, NS_SYMBOL);
 952                 sym->ctype.modifiers &= ~MOD_ADDRESSABLE;
 953                 sym->initializer = expr;
 954                 sym->enum_member = 1;
 955                 sym->ctype.base_type = parent;
 956                 add_ptr_list(&parent->symbol_list, sym);
 957 
 958                 if (base_type != &bad_ctype) {
 959                         if (ctype->type == SYM_NODE)
 960                                 ctype = ctype->ctype.base_type;
 961                         if (ctype->type == SYM_ENUM) {
 962                                 if (ctype == parent)
 963                                         ctype = base_type;
 964                                 else 
 965                                         ctype = ctype->ctype.base_type;
 966                         }
 967                         /*
 968                          * base_type rules:
 969                          *  - if all enums are of the same type, then
 970                          *    the base_type is that type (two first
 971                          *    cases)
 972                          *  - if enums are of different types, they
 973                          *    all have to be integer types, and the
 974                          *    base type is at least "int_ctype".
 975                          *  - otherwise the base_type is "bad_ctype".
 976                          */
 977                         if (!base_type || ctype == &bad_ctype) {
 978                                 base_type = ctype;
 979                         } else if (ctype == base_type) {
 980                                 /* nothing */
 981                         } else if (is_int_type(base_type) && is_int_type(ctype)) {
 982                                 base_type = &int_ctype;
 983                         } else if (is_restricted_type(base_type) != is_restricted_type(ctype)) {
 984                                 if (!mix_bitwise++) {
 985                                         warning(expr->pos, "mixed bitwiseness");
 986                                 }
 987                         } else if (is_restricted_type(base_type) && base_type != ctype) {
 988                                 sparse_error(expr->pos, "incompatible restricted type");
 989                                 info(expr->pos, "   expected: %s", show_typename(base_type));
 990                                 info(expr->pos, "        got: %s", show_typename(ctype));
 991                                 base_type = &bad_ctype;
 992                         } else if (base_type != &bad_ctype) {
 993                                 sparse_error(token->pos, "bad enum definition");
 994                                 base_type = &bad_ctype;
 995                         }
 996                         parent->ctype.base_type = base_type;
 997                 }
 998                 if (is_int_type(base_type)) {
 999                         update_range(&range, lastval, ctype);
1000                 }
1001                 token = next;
1002 
1003                 sym->endpos = token->pos;
1004 
1005                 if (!match_op(token, ','))
1006                         break;
1007                 token = token->next;
1008         }
1009         if (!base_type) {
1010                 sparse_error(token->pos, "empty enum definition");
1011                 base_type = &bad_ctype;
1012         }
1013         else if (!is_int_type(base_type))
1014                 ;
1015         else if (type_is_ok(&uint_ctype, range))
1016                 base_type = &uint_ctype;
1017         else if (type_is_ok(&int_ctype, range))
1018                 base_type = &int_ctype;
1019         else if (type_is_ok(&ulong_ctype, range))
1020                 base_type = &ulong_ctype;
1021         else if (type_is_ok(&long_ctype, range))
1022                 base_type = &long_ctype;
1023         else if (type_is_ok(&ullong_ctype, range))
1024                 base_type = &ullong_ctype;
1025         else if (type_is_ok(&llong_ctype, range))
1026                 base_type = &llong_ctype;
1027         else
1028                 base_type = &bad_ctype;
1029         parent->ctype.base_type = base_type;
1030         parent->ctype.modifiers |= (base_type->ctype.modifiers & MOD_UNSIGNED);
1031         parent->examined = 0;
1032 
1033         if (mix_bitwise)
1034                 return token;
1035         cast_enum_list(parent->symbol_list, base_type);
1036 
1037         return token;
1038 }
1039 
1040 static struct token *enum_specifier(struct token *token, struct decl_state *ctx)
1041 {
1042         struct token *ret = struct_union_enum_specifier(SYM_ENUM, token, ctx, parse_enum_declaration);
1043         struct ctype *ctype = &ctx->ctype.base_type->ctype;
1044 
1045         if (!ctype->base_type)
1046                 ctype->base_type = &incomplete_ctype;
1047 
1048         return ret;
1049 }
1050 
1051 static struct token *typeof_specifier(struct token *token, struct decl_state *ctx)
1052 {
1053         struct symbol *sym;
1054 
1055         if (!match_op(token, '(')) {
1056                 sparse_error(token->pos, "expected '(' after typeof");
1057                 return token;
1058         }
1059         if (lookup_type(token->next)) {
1060                 token = typename(token->next, &sym, NULL);
1061                 ctx->ctype.base_type = sym->ctype.base_type;
1062                 apply_ctype(token->pos, &sym->ctype, &ctx->ctype);
1063         } else {
1064                 struct symbol *typeof_sym = alloc_symbol(token->pos, SYM_TYPEOF);
1065                 token = parse_expression(token->next, &typeof_sym->initializer);
1066 
1067                 typeof_sym->endpos = token->pos;
1068                 if (!typeof_sym->initializer) {
1069                         sparse_error(token->pos, "expected expression after the '(' token");
1070                         typeof_sym = &bad_ctype;
1071                 }
1072                 ctx->ctype.base_type = typeof_sym;
1073         }
1074         return expect(token, ')', "after typeof");
1075 }
1076 
1077 static struct token *ignore_attribute(struct token *token, struct symbol *attr, struct decl_state *ctx)
1078 {
1079         struct expression *expr = NULL;
1080         if (match_op(token, '('))
1081                 token = parens_expression(token, &expr, "in attribute");
1082         return token;
1083 }
1084 
1085 static struct token *attribute_packed(struct token *token, struct symbol *attr, struct decl_state *ctx)
1086 {
1087         if (!ctx->ctype.alignment)
1088                 ctx->ctype.alignment = 1;
1089         return token;
1090 }
1091 
1092 static struct token *attribute_aligned(struct token *token, struct symbol *attr, struct decl_state *ctx)
1093 {
1094         int alignment = max_alignment;
1095         struct expression *expr = NULL;
1096 
1097         if (match_op(token, '(')) {
1098                 token = parens_expression(token, &expr, "in attribute");
1099                 if (expr)
1100                         alignment = const_expression_value(expr);
1101         }
1102         if (alignment & (alignment-1)) {
1103                 warning(token->pos, "I don't like non-power-of-2 alignments");
1104                 return token;
1105         } else if (alignment > ctx->ctype.alignment)
1106                 ctx->ctype.alignment = alignment;
1107         return token;
1108 }
1109 
1110 static void apply_qualifier(struct position *pos, struct ctype *ctx, unsigned long qual)
1111 {
1112         if (ctx->modifiers & qual)
1113                 warning(*pos, "duplicate %s", modifier_string(qual));
1114         ctx->modifiers |= qual;
1115 }
1116 
1117 static struct token *attribute_modifier(struct token *token, struct symbol *attr, struct decl_state *ctx)
1118 {
1119         apply_qualifier(&token->pos, &ctx->ctype, attr->ctype.modifiers);
1120         return token;
1121 }
1122 
1123 static struct token *attribute_ext_visible(struct token *token, struct symbol *attr, struct decl_state *ctx)
1124 {
1125         ctx->is_ext_visible = 1;
1126         return token;
1127 }
1128 
1129 static struct token *attribute_bitwise(struct token *token, struct symbol *attr, struct decl_state *ctx)
1130 {
1131         if (Wbitwise)
1132                 attribute_modifier(token, attr, ctx);
1133         return token;
1134 }
1135 
1136 static struct ident *numerical_address_space(int asn)
1137 {
1138         char buff[32];
1139 
1140         if (!asn)
1141                 return NULL;
1142         sprintf(buff, "<asn:%d>", asn);
1143         return built_in_ident(buff);
1144 }
1145 
1146 static struct token *attribute_address_space(struct token *token, struct symbol *attr, struct decl_state *ctx)
1147 {
1148         struct expression *expr = NULL;
1149         struct ident *as = NULL;
1150         struct token *next;
1151 
1152         token = expect(token, '(', "after address_space attribute");
1153         switch (token_type(token)) {
1154         case TOKEN_NUMBER:
1155                 next = primary_expression(token, &expr);
1156                 if (expr->type != EXPR_VALUE)
1157                         goto invalid;
1158                 as = numerical_address_space(expr->value);
1159                 break;
1160         case TOKEN_IDENT:
1161                 next = token->next;
1162                 as = token->ident;
1163                 break;
1164         default:
1165                 next = token->next;
1166         invalid:
1167                 as = NULL;
1168                 warning(token->pos, "invalid address space name");
1169         }
1170 
1171         if (Waddress_space && as) {
1172                 if (ctx->ctype.as)
1173                         sparse_error(token->pos,
1174                                      "multiple address space given: %s & %s",
1175                                      show_as(ctx->ctype.as), show_as(as));
1176                 ctx->ctype.as = as;
1177         }
1178         token = expect(next, ')', "after address_space attribute");
1179         return token;
1180 }
1181 
1182 static struct symbol *to_QI_mode(struct symbol *ctype)
1183 {
1184         if (ctype->ctype.base_type != &int_type)
1185                 return NULL;
1186         if (ctype == &char_ctype)
1187                 return ctype;
1188         return ctype->ctype.modifiers & MOD_UNSIGNED ? &uchar_ctype
1189                                                      : &schar_ctype;
1190 }
1191 
1192 static struct symbol *to_HI_mode(struct symbol *ctype)
1193 {
1194         if (ctype->ctype.base_type != &int_type)
1195                 return NULL;
1196         return ctype->ctype.modifiers & MOD_UNSIGNED ? &ushort_ctype
1197                                                      : &sshort_ctype;
1198 }
1199 
1200 static struct symbol *to_SI_mode(struct symbol *ctype)
1201 {
1202         if (ctype->ctype.base_type != &int_type)
1203                 return NULL;
1204         return ctype->ctype.modifiers & MOD_UNSIGNED ? &uint_ctype
1205                                                      : &sint_ctype;
1206 }
1207 
1208 static struct symbol *to_DI_mode(struct symbol *ctype)
1209 {
1210         if (ctype->ctype.base_type != &int_type)
1211                 return NULL;
1212         return ctype->ctype.modifiers & MOD_UNSIGNED ? &ullong_ctype
1213                                                      : &sllong_ctype;
1214 }
1215 
1216 static struct symbol *to_TI_mode(struct symbol *ctype)
1217 {
1218         if (ctype->ctype.base_type != &int_type)
1219                 return NULL;
1220         return ctype->ctype.modifiers & MOD_UNSIGNED ? &ulllong_ctype
1221                                                      : &slllong_ctype;
1222 }
1223 
1224 static struct symbol *to_pointer_mode(struct symbol *ctype)
1225 {
1226         if (ctype->ctype.base_type != &int_type)
1227                 return NULL;
1228         return ctype->ctype.modifiers & MOD_UNSIGNED ? uintptr_ctype
1229                                                      :  intptr_ctype;
1230 }
1231 
1232 static struct symbol *to_word_mode(struct symbol *ctype)
1233 {
1234         if (ctype->ctype.base_type != &int_type)
1235                 return NULL;
1236         return ctype->ctype.modifiers & MOD_UNSIGNED ? &ulong_ctype
1237                                                      : &slong_ctype;
1238 }
1239 
1240 static struct token *attribute_mode(struct token *token, struct symbol *attr, struct decl_state *ctx)
1241 {
1242         token = expect(token, '(', "after mode attribute");
1243         if (token_type(token) == TOKEN_IDENT) {
1244                 struct symbol *mode = lookup_keyword(token->ident, NS_KEYWORD);
1245                 if (mode && mode->op->type == KW_MODE)
1246                         ctx->mode = mode->op;
1247                 else
1248                         sparse_error(token->pos, "unknown mode attribute %s", show_ident(token->ident));
1249                 token = token->next;
1250         } else
1251                 sparse_error(token->pos, "expect attribute mode symbol\n");
1252         token = expect(token, ')', "after mode attribute");
1253         return token;
1254 }
1255 
1256 static struct token *attribute_context(struct token *token, struct symbol *attr, struct decl_state *ctx)
1257 {
1258         struct context *context = alloc_context();
1259         struct expression *args[3];
1260         int idx = 0;
1261 
1262         token = expect(token, '(', "after context attribute");
1263         token = conditional_expression(token, &args[0]);
1264         token = expect(token, ',', "after context 1st argument");
1265         token = conditional_expression(token, &args[1]);
1266         if (match_op(token, ',')) {
1267                 token = token->next;
1268                 token = conditional_expression(token, &args[2]);
1269                 token = expect(token, ')', "after context 3rd argument");
1270                 context->context = args[0];
1271                 idx++;
1272         } else {
1273                 token = expect(token, ')', "after context 2nd argument");
1274         }
1275         context->in =  get_expression_value(args[idx++]);
1276         context->out = get_expression_value(args[idx++]);
1277         add_ptr_list(&ctx->ctype.contexts, context);
1278         return token;
1279 }
1280 
1281 static struct token *attribute_designated_init(struct token *token, struct symbol *attr, struct decl_state *ctx)
1282 {
1283         if (ctx->ctype.base_type && ctx->ctype.base_type->type == SYM_STRUCT)
1284                 ctx->ctype.base_type->designated_init = 1;
1285         else
1286                 warning(token->pos, "attribute designated_init applied to non-structure type");
1287         return token;
1288 }
1289 
1290 static struct token *attribute_transparent_union(struct token *token, struct symbol *attr, struct decl_state *ctx)
1291 {
1292         if (Wtransparent_union)
1293                 warning(token->pos, "attribute __transparent_union__");
1294 
1295         if (ctx->ctype.base_type && ctx->ctype.base_type->type == SYM_UNION)
1296                 ctx->ctype.base_type->transparent_union = 1;
1297         else
1298                 warning(token->pos, "attribute __transparent_union__ applied to non-union type");
1299         return token;
1300 }
1301 
1302 static struct token *recover_unknown_attribute(struct token *token)
1303 {
1304         struct expression *expr = NULL;
1305 
1306         if (Wunknown_attribute)
1307                 warning(token->pos, "unknown attribute '%s'", show_ident(token->ident));
1308         token = token->next;
1309         if (match_op(token, '('))
1310                 token = parens_expression(token, &expr, "in attribute");
1311         return token;
1312 }
1313 
1314 static struct token *attribute_specifier(struct token *token, struct decl_state *ctx)
1315 {
1316         token = expect(token, '(', "after attribute");
1317         token = expect(token, '(', "after attribute");
1318 
1319         for (;;) {
1320                 struct ident *attribute_name;
1321                 struct symbol *attr;
1322 
1323                 if (eof_token(token))
1324                         break;
1325                 if (match_op(token, ';'))
1326                         break;
1327                 if (token_type(token) != TOKEN_IDENT)
1328                         break;
1329                 attribute_name = token->ident;
1330                 attr = lookup_keyword(attribute_name, NS_KEYWORD);
1331                 if (attr && attr->op->attribute)
1332                         token = attr->op->attribute(token->next, attr, ctx);
1333                 else
1334                         token = recover_unknown_attribute(token);
1335 
1336                 if (!match_op(token, ','))
1337                         break;
1338                 token = token->next;
1339         }
1340 
1341         token = expect(token, ')', "after attribute");
1342         token = expect(token, ')', "after attribute");
1343         return token;
1344 }
1345 
1346 static const char *storage_class[] = 
1347 {
1348         [STypedef] = "typedef",
1349         [SAuto] = "auto",
1350         [SExtern] = "extern",
1351         [SStatic] = "static",
1352         [SRegister] = "register",
1353         [SForced] = "[force]"
1354 };
1355 
1356 static unsigned long storage_modifiers(struct decl_state *ctx)
1357 {
1358         static unsigned long mod[SMax] =
1359         {
1360                 [SAuto] = MOD_AUTO,
1361                 [SExtern] = MOD_EXTERN,
1362                 [SStatic] = MOD_STATIC,
1363                 [SRegister] = MOD_REGISTER
1364         };
1365         return mod[ctx->storage_class] | (ctx->is_inline ? MOD_INLINE : 0)
1366                 | (ctx->is_tls ? MOD_TLS : 0)
1367                 | (ctx->is_ext_visible ? MOD_EXT_VISIBLE : 0);
1368 }
1369 
1370 static void set_storage_class(struct position *pos, struct decl_state *ctx, int class)
1371 {
1372         /* __thread can be used alone, or with extern or static */
1373         if (ctx->is_tls && (class != SStatic && class != SExtern)) {
1374                 sparse_error(*pos, "__thread can only be used alone, or with "
1375                                 "extern or static");
1376                 return;
1377         }
1378 
1379         if (!ctx->storage_class) {
1380                 ctx->storage_class = class;
1381                 return;
1382         }
1383         if (ctx->storage_class == class)
1384                 sparse_error(*pos, "duplicate %s", storage_class[class]);
1385         else
1386                 sparse_error(*pos, "multiple storage classes");
1387 }
1388 
1389 static struct token *typedef_specifier(struct token *next, struct decl_state *ctx)
1390 {
1391         set_storage_class(&next->pos, ctx, STypedef);
1392         return next;
1393 }
1394 
1395 static struct token *auto_specifier(struct token *next, struct decl_state *ctx)
1396 {
1397         set_storage_class(&next->pos, ctx, SAuto);
1398         return next;
1399 }
1400 
1401 static struct token *register_specifier(struct token *next, struct decl_state *ctx)
1402 {
1403         set_storage_class(&next->pos, ctx, SRegister);
1404         return next;
1405 }
1406 
1407 static struct token *static_specifier(struct token *next, struct decl_state *ctx)
1408 {
1409         set_storage_class(&next->pos, ctx, SStatic);
1410         return next;
1411 }
1412 
1413 static struct token *extern_specifier(struct token *next, struct decl_state *ctx)
1414 {
1415         set_storage_class(&next->pos, ctx, SExtern);
1416         return next;
1417 }
1418 
1419 static struct token *thread_specifier(struct token *next, struct decl_state *ctx)
1420 {
1421         /* This GCC extension can be used alone, or with extern or static */
1422         if (!ctx->storage_class || ctx->storage_class == SStatic
1423                         || ctx->storage_class == SExtern) {
1424                 ctx->is_tls = 1;
1425         } else {
1426                 sparse_error(next->pos, "__thread can only be used alone, or "
1427                                 "with extern or static");
1428         }
1429 
1430         return next;
1431 }
1432 
1433 static struct token *attribute_force(struct token *token, struct symbol *attr, struct decl_state *ctx)
1434 {
1435         set_storage_class(&token->pos, ctx, SForced);
1436         return token;
1437 }
1438 
1439 static struct token *inline_specifier(struct token *next, struct decl_state *ctx)
1440 {
1441         ctx->is_inline = 1;
1442         return next;
1443 }
1444 
1445 static struct token *noreturn_specifier(struct token *next, struct decl_state *ctx)
1446 {
1447         apply_qualifier(&next->pos, &ctx->ctype, MOD_NORETURN);
1448         return next;
1449 }
1450 
1451 static struct token *alignas_specifier(struct token *token, struct decl_state *ctx)
1452 {
1453         int alignment = 0;
1454 
1455         if (!match_op(token, '(')) {
1456                 sparse_error(token->pos, "expected '(' after _Alignas");
1457                 return token;
1458         }
1459         if (lookup_type(token->next)) {
1460                 struct symbol *sym = NULL;
1461                 token = typename(token->next, &sym, NULL);
1462                 sym = examine_symbol_type(sym);
1463                 alignment = sym->ctype.alignment;
1464                 token = expect(token, ')', "after _Alignas(...");
1465         } else {
1466                 struct expression *expr = NULL;
1467                 token = parens_expression(token, &expr, "after _Alignas");
1468                 if (!expr)
1469                         return token;
1470                 alignment = const_expression_value(expr);
1471         }
1472 
1473         if (alignment < 0) {
1474                 warning(token->pos, "non-positive alignment");
1475                 return token;
1476         }
1477         if (alignment & (alignment-1)) {
1478                 warning(token->pos, "non-power-of-2 alignment");
1479                 return token;
1480         }
1481         if (alignment > ctx->ctype.alignment)
1482                 ctx->ctype.alignment = alignment;
1483         return token;
1484 }
1485 
1486 static struct token *const_qualifier(struct token *next, struct decl_state *ctx)
1487 {
1488         apply_qualifier(&next->pos, &ctx->ctype, MOD_CONST);
1489         return next;
1490 }
1491 
1492 static struct token *volatile_qualifier(struct token *next, struct decl_state *ctx)
1493 {
1494         apply_qualifier(&next->pos, &ctx->ctype, MOD_VOLATILE);
1495         return next;
1496 }
1497 
1498 static struct token *restrict_qualifier(struct token *next, struct decl_state *ctx)
1499 {
1500         apply_qualifier(&next->pos, &ctx->ctype, MOD_RESTRICT);
1501         return next;
1502 }
1503 
1504 static struct token *atomic_qualifier(struct token *next, struct decl_state *ctx)
1505 {
1506         apply_qualifier(&next->pos, &ctx->ctype, MOD_ATOMIC);
1507         return next;
1508 }
1509 
1510 static void apply_ctype(struct position pos, struct ctype *thistype, struct ctype *ctype)
1511 {
1512         unsigned long mod = thistype->modifiers;
1513 
1514         if (mod)
1515                 apply_qualifier(&pos, ctype, mod);
1516 
1517         /* Context */
1518         concat_ptr_list((struct ptr_list *)thistype->contexts,
1519                         (struct ptr_list **)&ctype->contexts);
1520 
1521         /* Alignment */
1522         if (thistype->alignment > ctype->alignment)
1523                 ctype->alignment = thistype->alignment;
1524 
1525         /* Address space */
1526         if (thistype->as)
1527                 ctype->as = thistype->as;
1528 }
1529 
1530 static void specifier_conflict(struct position pos, int what, struct ident *new)
1531 {
1532         const char *old;
1533         if (what & (Set_S | Set_T))
1534                 goto Catch_all;
1535         if (what & Set_Char)
1536                 old = "char";
1537         else if (what & Set_Double)
1538                 old = "double";
1539         else if (what & Set_Float)
1540                 old = "float";
1541         else if (what & Set_Signed)
1542                 old = "signed";
1543         else if (what & Set_Unsigned)
1544                 old = "unsigned";
1545         else if (what & Set_Short)
1546                 old = "short";
1547         else if (what & Set_Long)
1548                 old = "long";
1549         else
1550                 old = "long long";
1551         sparse_error(pos, "impossible combination of type specifiers: %s %s",
1552                         old, show_ident(new));
1553         return;
1554 
1555 Catch_all:
1556         sparse_error(pos, "two or more data types in declaration specifiers");
1557 }
1558 
1559 static struct symbol * const int_types[] =
1560         {&short_ctype, &int_ctype, &long_ctype, &llong_ctype, &lllong_ctype};
1561 static struct symbol * const signed_types[] =
1562         {&sshort_ctype, &sint_ctype, &slong_ctype, &sllong_ctype,
1563          &slllong_ctype};
1564 static struct symbol * const unsigned_types[] =
1565         {&ushort_ctype, &uint_ctype, &ulong_ctype, &ullong_ctype,
1566          &ulllong_ctype};
1567 static struct symbol * const real_types[] =
1568         {&float_ctype, &double_ctype, &ldouble_ctype};
1569 static struct symbol * const char_types[] =
1570         {&char_ctype, &schar_ctype, &uchar_ctype};
1571 static struct symbol * const * const types[] = {
1572         int_types + 1, signed_types + 1, unsigned_types + 1,
1573         real_types + 1, char_types, char_types + 1, char_types + 2
1574 };
1575 
1576 struct symbol *ctype_integer(int size, int want_unsigned)
1577 {
1578         return types[want_unsigned ? CUInt : CInt][size];
1579 }
1580 
1581 static struct token *handle_qualifiers(struct token *t, struct decl_state *ctx)
1582 {
1583         while (token_type(t) == TOKEN_IDENT) {
1584                 struct symbol *s = lookup_symbol(t->ident, NS_TYPEDEF);
1585                 if (!s)
1586                         break;
1587                 if (s->type != SYM_KEYWORD)
1588                         break;
1589                 if (!(s->op->type & (KW_ATTRIBUTE | KW_QUALIFIER)))
1590                         break;
1591                 t = t->next;
1592                 if (s->op->declarator)
1593                         t = s->op->declarator(t, ctx);
1594         }
1595         return t;
1596 }
1597 
1598 static struct token *declaration_specifiers(struct token *token, struct decl_state *ctx)
1599 {
1600         int seen = 0;
1601         int class = CInt;
1602         int size = 0;
1603 
1604         while (token_type(token) == TOKEN_IDENT) {
1605                 struct symbol *s = lookup_symbol(token->ident,
1606                                                  NS_TYPEDEF | NS_SYMBOL);
1607                 if (!s || !(s->namespace & NS_TYPEDEF))
1608                         break;
1609                 if (s->type != SYM_KEYWORD) {
1610                         if (seen & Set_Any)
1611                                 break;
1612                         seen |= Set_S | Set_T;
1613                         ctx->ctype.base_type = s->ctype.base_type;
1614                         apply_ctype(token->pos, &s->ctype, &ctx->ctype);
1615                         token = token->next;
1616                         continue;
1617                 }
1618                 if (s->op->type & KW_SPECIFIER) {
1619                         if (seen & s->op->test) {
1620                                 specifier_conflict(token->pos,
1621                                                    seen & s->op->test,
1622                                                    token->ident);
1623                                 break;
1624                         }
1625                         seen |= s->op->set;
1626                         class += s->op->class;
1627                         if (s->op->set & Set_Int128)
1628                                 size = 2;
1629                         if (s->op->type & KW_SHORT) {
1630                                 size = -1;
1631                         } else if (s->op->type & KW_LONG && size++) {
1632                                 if (class == CReal) {
1633                                         specifier_conflict(token->pos,
1634                                                            Set_Vlong,
1635                                                            &double_ident);
1636                                         break;
1637                                 }
1638                                 seen |= Set_Vlong;
1639                         }
1640                 }
1641                 token = token->next;
1642                 if (s->op->declarator)
1643                         token = s->op->declarator(token, ctx);
1644                 if (s->op->type & KW_EXACT) {
1645                         ctx->ctype.base_type = s->ctype.base_type;
1646                         ctx->ctype.modifiers |= s->ctype.modifiers;
1647                 }
1648         }
1649 
1650         if (!(seen & Set_S)) {      /* not set explicitly? */
1651                 struct symbol *base = &incomplete_ctype;
1652                 if (seen & Set_Any)
1653                         base = types[class][size];
1654                 ctx->ctype.base_type = base;
1655         }
1656 
1657         if (ctx->ctype.modifiers & MOD_BITWISE) {
1658                 struct symbol *type;
1659                 ctx->ctype.modifiers &= ~MOD_BITWISE;
1660                 if (!is_int_type(ctx->ctype.base_type)) {
1661                         sparse_error(token->pos, "invalid modifier");
1662                         return token;
1663                 }
1664                 type = alloc_symbol(token->pos, SYM_BASETYPE);
1665                 *type = *ctx->ctype.base_type;
1666                 type->ctype.modifiers &= ~MOD_SPECIFIER;
1667                 type->ctype.base_type = ctx->ctype.base_type;
1668                 type->type = SYM_RESTRICT;
1669                 ctx->ctype.base_type = type;
1670                 create_fouled(type);
1671         }
1672         return token;
1673 }
1674 
1675 static struct token *abstract_array_static_declarator(struct token *token, int *has_static)
1676 {
1677         while (token->ident == &static_ident) {
1678                 if (*has_static)
1679                         sparse_error(token->pos, "duplicate array static declarator");
1680 
1681                 *has_static = 1;
1682                 token = token->next;
1683         }
1684         return token;
1685 
1686 }
1687 
1688 static struct token *abstract_array_declarator(struct token *token, struct symbol *sym)
1689 {
1690         struct expression *expr = NULL;
1691         int has_static = 0;
1692 
1693         token = abstract_array_static_declarator(token, &has_static);
1694 
1695         if (match_idents(token, &restrict_ident, &__restrict_ident, &__restrict___ident, NULL))
1696                 token = abstract_array_static_declarator(token->next, &has_static);
1697         token = parse_expression(token, &expr);
1698         sym->array_size = expr;
1699         return token;
1700 }
1701 
1702 static struct token *parameter_type_list(struct token *, struct symbol *);
1703 static struct token *identifier_list(struct token *, struct symbol *);
1704 static struct token *declarator(struct token *token, struct decl_state *ctx);
1705 
1706 static struct token *skip_attribute(struct token *token)
1707 {
1708         token = token->next;
1709         if (match_op(token, '(')) {
1710                 int depth = 1;
1711                 token = token->next;
1712                 while (depth && !eof_token(token)) {
1713                         if (token_type(token) == TOKEN_SPECIAL) {
1714                                 if (token->special == '(')
1715                                         depth++;
1716                                 else if (token->special == ')')
1717                                         depth--;
1718                         }
1719                         token = token->next;
1720                 }
1721         }
1722         return token;
1723 }
1724 
1725 static struct token *skip_attributes(struct token *token)
1726 {
1727         struct symbol *keyword;
1728         for (;;) {
1729                 if (token_type(token) != TOKEN_IDENT)
1730                         break;
1731                 keyword = lookup_keyword(token->ident, NS_KEYWORD | NS_TYPEDEF);
1732                 if (!keyword || keyword->type != SYM_KEYWORD)
1733                         break;
1734                 if (!(keyword->op->type & KW_ATTRIBUTE))
1735                         break;
1736                 token = expect(token->next, '(', "after attribute");
1737                 token = expect(token, '(', "after attribute");
1738                 for (;;) {
1739                         if (eof_token(token))
1740                                 break;
1741                         if (match_op(token, ';'))
1742                                 break;
1743                         if (token_type(token) != TOKEN_IDENT)
1744                                 break;
1745                         token = skip_attribute(token);
1746                         if (!match_op(token, ','))
1747                                 break;
1748                         token = token->next;
1749                 }
1750                 token = expect(token, ')', "after attribute");
1751                 token = expect(token, ')', "after attribute");
1752         }
1753         return token;
1754 }
1755 
1756 static struct token *handle_attributes(struct token *token, struct decl_state *ctx, unsigned int keywords)
1757 {
1758         struct symbol *keyword;
1759         for (;;) {
1760                 if (token_type(token) != TOKEN_IDENT)
1761                         break;
1762                 keyword = lookup_keyword(token->ident, NS_KEYWORD | NS_TYPEDEF);
1763                 if (!keyword || keyword->type != SYM_KEYWORD)
1764                         break;
1765                 if (!(keyword->op->type & keywords))
1766                         break;
1767                 token = keyword->op->declarator(token->next, ctx);
1768                 keywords &= KW_ATTRIBUTE;
1769         }
1770         return token;
1771 }
1772 
1773 static int is_nested(struct token *token, struct token **p,
1774                     int prefer_abstract)
1775 {
1776         /*
1777          * This can be either a parameter list or a grouping.
1778          * For the direct (non-abstract) case, we know if must be
1779          * a parameter list if we already saw the identifier.
1780          * For the abstract case, we know if must be a parameter
1781          * list if it is empty or starts with a type.
1782          */
1783         struct token *next = token->next;
1784 
1785         *p = next = skip_attributes(next);
1786 
1787         if (token_type(next) == TOKEN_IDENT) {
1788                 if (lookup_type(next))
1789                         return !prefer_abstract;
1790                 return 1;
1791         }
1792 
1793         if (match_op(next, ')') || match_op(next, SPECIAL_ELLIPSIS))
1794                 return 0;
1795 
1796         return 1;
1797 }
1798 
1799 enum kind {
1800         Empty, K_R, Proto, Bad_Func,
1801 };
1802 
1803 static enum kind which_func(struct token *token,
1804                             struct ident **n,
1805                             int prefer_abstract)
1806 {
1807         struct token *next = token->next;
1808 
1809         if (token_type(next) == TOKEN_IDENT) {
1810                 if (lookup_type(next))
1811                         return Proto;
1812                 /* identifier list not in definition; complain */
1813                 if (prefer_abstract)
1814                         warning(token->pos,
1815                                 "identifier list not in definition");
1816                 return K_R;
1817         }
1818 
1819         if (token_type(next) != TOKEN_SPECIAL)
1820                 return Bad_Func;
1821 
1822         if (next->special == ')') {
1823                 /* don't complain about those */
1824                 if (!n || match_op(next->next, ';') || match_op(next->next, ','))
1825                         return Empty;
1826                 if (Wstrict_prototypes)
1827                         warning(next->pos,
1828                                 "non-ANSI function declaration of function '%s'",
1829                                 show_ident(*n));
1830                 return Empty;
1831         }
1832 
1833         if (next->special == SPECIAL_ELLIPSIS) {
1834                 warning(next->pos,
1835                         "variadic functions must have one named argument");
1836                 return Proto;
1837         }
1838 
1839         return Bad_Func;
1840 }
1841 
1842 static struct token *direct_declarator(struct token *token, struct decl_state *ctx)
1843 {
1844         struct ctype *ctype = &ctx->ctype;
1845         struct token *next;
1846         struct ident **p = ctx->ident;
1847 
1848         if (ctx->ident && token_type(token) == TOKEN_IDENT) {
1849                 *ctx->ident = token->ident;
1850                 token = token->next;
1851         } else if (match_op(token, '(') &&
1852             is_nested(token, &next, ctx->prefer_abstract)) {
1853                 struct symbol *base_type = ctype->base_type;
1854                 if (token->next != next)
1855                         next = handle_attributes(token->next, ctx,
1856                                                   KW_ATTRIBUTE);
1857                 token = declarator(next, ctx);
1858                 token = expect(token, ')', "in nested declarator");
1859                 while (ctype->base_type != base_type)
1860                         ctype = &ctype->base_type->ctype;
1861                 p = NULL;
1862         }
1863 
1864         if (match_op(token, '(')) {
1865                 enum kind kind = which_func(token, p, ctx->prefer_abstract);
1866                 struct symbol *fn;
1867                 fn = alloc_indirect_symbol(token->pos, ctype, SYM_FN);
1868                 token = token->next;
1869                 if (kind == K_R)
1870                         token = identifier_list(token, fn);
1871                 else if (kind == Proto)
1872                         token = parameter_type_list(token, fn);
1873                 token = expect(token, ')', "in function declarator");
1874                 fn->endpos = token->pos;
1875                 return token;
1876         }
1877 
1878         while (match_op(token, '[')) {
1879                 struct symbol *array;
1880                 array = alloc_indirect_symbol(token->pos, ctype, SYM_ARRAY);
1881                 token = abstract_array_declarator(token->next, array);
1882                 token = expect(token, ']', "in abstract_array_declarator");
1883                 array->endpos = token->pos;
1884                 ctype = &array->ctype;
1885         }
1886         return token;
1887 }
1888 
1889 static struct token *pointer(struct token *token, struct decl_state *ctx)
1890 {
1891         while (match_op(token,'*')) {
1892                 struct symbol *ptr = alloc_symbol(token->pos, SYM_PTR);
1893                 ptr->ctype.modifiers = ctx->ctype.modifiers;
1894                 ptr->ctype.base_type = ctx->ctype.base_type;
1895                 ptr->ctype.as = ctx->ctype.as;
1896                 ptr->ctype.contexts = ctx->ctype.contexts;
1897                 ctx->ctype.modifiers = 0;
1898                 ctx->ctype.base_type = ptr;
1899                 ctx->ctype.as = NULL;
1900                 ctx->ctype.contexts = NULL;
1901                 ctx->ctype.alignment = 0;
1902 
1903                 token = handle_qualifiers(token->next, ctx);
1904                 ctx->ctype.base_type->endpos = token->pos;
1905         }
1906         return token;
1907 }
1908 
1909 static struct token *declarator(struct token *token, struct decl_state *ctx)
1910 {
1911         token = pointer(token, ctx);
1912         return direct_declarator(token, ctx);
1913 }
1914 
1915 static struct token *handle_bitfield(struct token *token, struct decl_state *ctx)
1916 {
1917         struct ctype *ctype = &ctx->ctype;
1918         struct expression *expr;
1919         struct symbol *bitfield;
1920         long long width;
1921 
1922         if (ctype->base_type != &int_type && !is_int_type(ctype->base_type)) {
1923                 sparse_error(token->pos, "invalid bitfield specifier for type %s.",
1924                         show_typename(ctype->base_type));
1925                 // Parse this to recover gracefully.
1926                 return conditional_expression(token->next, &expr);
1927         }
1928 
1929         bitfield = alloc_indirect_symbol(token->pos, ctype, SYM_BITFIELD);
1930         token = conditional_expression(token->next, &expr);
1931         width = const_expression_value(expr);
1932         bitfield->bit_size = width;
1933 
1934         if (width < 0 || width > INT_MAX) {
1935                 sparse_error(token->pos, "invalid bitfield width, %lld.", width);
1936                 width = -1;
1937         } else if (*ctx->ident && width == 0) {
1938                 sparse_error(token->pos, "invalid named zero-width bitfield `%s'",
1939                      show_ident(*ctx->ident));
1940                 width = -1;
1941         } else if (*ctx->ident) {
1942                 struct symbol *base_type = bitfield->ctype.base_type;
1943                 struct symbol *bitfield_type = base_type == &int_type ? bitfield : base_type;
1944                 int is_signed = !(bitfield_type->ctype.modifiers & MOD_UNSIGNED);
1945                 if (Wone_bit_signed_bitfield && width == 1 && is_signed) {
1946                         // Valid values are either {-1;0} or {0}, depending on integer
1947                         // representation.  The latter makes for very efficient code...
1948                         sparse_error(token->pos, "dubious one-bit signed bitfield");
1949                 }
1950                 if (Wdefault_bitfield_sign &&
1951                     bitfield_type->type != SYM_ENUM &&
1952                     !(bitfield_type->ctype.modifiers & MOD_EXPLICITLY_SIGNED) &&
1953                     is_signed) {
1954                         // The sign of bitfields is unspecified by default.
1955                         warning(token->pos, "dubious bitfield without explicit `signed' or `unsigned'");
1956                 }
1957         }
1958         bitfield->bit_size = width;
1959         bitfield->endpos = token->pos;
1960         return token;
1961 }
1962 
1963 static struct token *declaration_list(struct token *token, struct symbol_list **list)
1964 {
1965         struct decl_state ctx = {.prefer_abstract = 0};
1966         struct ctype saved;
1967         unsigned long mod;
1968 
1969         token = declaration_specifiers(token, &ctx);
1970         mod = storage_modifiers(&ctx);
1971         saved = ctx.ctype;
1972         for (;;) {
1973                 struct symbol *decl = alloc_symbol(token->pos, SYM_NODE);
1974                 ctx.ident = &decl->ident;
1975 
1976                 token = declarator(token, &ctx);
1977                 if (match_op(token, ':'))
1978                         token = handle_bitfield(token, &ctx);
1979 
1980                 token = handle_attributes(token, &ctx, KW_ATTRIBUTE);
1981                 apply_modifiers(token->pos, &ctx);
1982 
1983                 decl->ctype = ctx.ctype;
1984                 decl->ctype.modifiers |= mod;
1985                 decl->endpos = token->pos;
1986                 add_symbol(list, decl);
1987                 if (!match_op(token, ','))
1988                         break;
1989                 token = token->next;
1990                 ctx.ctype = saved;
1991         }
1992         return token;
1993 }
1994 
1995 static struct token *struct_declaration_list(struct token *token, struct symbol_list **list)
1996 {
1997         while (!match_op(token, '}')) {
1998                 if (match_ident(token, &_Static_assert_ident)) {
1999                         token = parse_static_assert(token, NULL);
2000                         continue;
2001                 }
2002                 if (!match_op(token, ';'))
2003                         token = declaration_list(token, list);
2004                 if (!match_op(token, ';')) {
2005                         sparse_error(token->pos, "expected ; at end of declaration");
2006                         break;
2007                 }
2008                 token = token->next;
2009         }
2010         return token;
2011 }
2012 
2013 static struct token *parameter_declaration(struct token *token, struct symbol *sym)
2014 {
2015         struct decl_state ctx = {.prefer_abstract = 1};
2016 
2017         token = declaration_specifiers(token, &ctx);
2018         ctx.ident = &sym->ident;
2019         token = declarator(token, &ctx);
2020         token = handle_attributes(token, &ctx, KW_ATTRIBUTE);
2021         apply_modifiers(token->pos, &ctx);
2022         sym->ctype = ctx.ctype;
2023         sym->ctype.modifiers |= storage_modifiers(&ctx);
2024         sym->endpos = token->pos;
2025         sym->forced_arg = ctx.storage_class == SForced;
2026         return token;
2027 }
2028 
2029 struct token *typename(struct token *token, struct symbol **p, int *forced)
2030 {
2031         struct decl_state ctx = {.prefer_abstract = 1};
2032         int class;
2033         struct symbol *sym = alloc_symbol(token->pos, SYM_NODE);
2034         *p = sym;
2035         token = declaration_specifiers(token, &ctx);
2036         token = declarator(token, &ctx);
2037         apply_modifiers(token->pos, &ctx);
2038         sym->ctype = ctx.ctype;
2039         sym->endpos = token->pos;
2040         class = ctx.storage_class;
2041         if (forced) {
2042                 *forced = 0;
2043                 if (class == SForced) {
2044                         *forced = 1;
2045                         class = 0;
2046                 }
2047         }
2048         if (class)
2049                 warning(sym->pos, "storage class in typename (%s %s)",
2050                         storage_class[class], show_typename(sym));
2051         return token;
2052 }
2053 
2054 static struct token *parse_underscore_Pragma(struct token *token)
2055 {
2056         struct token *next;
2057 
2058         next = token->next;
2059         if (!match_op(next, '('))
2060                 return next;
2061         next = next->next;
2062         if (next->pos.type != TOKEN_STRING)
2063                 return next;
2064         next = next->next;
2065         if (!match_op(next, ')'))
2066                 return next;
2067         return next->next;
2068 }
2069 
2070 static struct token *expression_statement(struct token *token, struct expression **tree)
2071 {
2072         if (match_ident(token, &_Pragma_ident))
2073                 return parse_underscore_Pragma(token);
2074 
2075         token = parse_expression(token, tree);
2076         return expect(token, ';', "at end of statement");
2077 }
2078 
2079 static struct token *parse_asm_operands(struct token *token, struct statement *stmt,
2080         struct expression_list **inout)
2081 {
2082         /* Allow empty operands */
2083         if (match_op(token->next, ':') || match_op(token->next, ')'))
2084                 return token->next;
2085         do {
2086                 struct expression *op = alloc_expression(token->pos, EXPR_ASM_OPERAND);
2087                 if (match_op(token->next, '[') &&
2088                     token_type(token->next->next) == TOKEN_IDENT &&
2089                     match_op(token->next->next->next, ']')) {
2090                         op->name = token->next->next->ident;
2091                         token = token->next->next->next;
2092                 }
2093                 token = primary_expression(token->next, &op->constraint);
2094                 token = parens_expression(token, &op->expr, "in asm parameter");
2095                 add_expression(inout, op);
2096         } while (match_op(token, ','));
2097         return token;
2098 }
2099 
2100 static struct token *parse_asm_clobbers(struct token *token, struct statement *stmt,
2101         struct expression_list **clobbers)
2102 {
2103         struct expression *expr;
2104 
2105         do {
2106                 token = primary_expression(token->next, &expr);
2107                 if (expr)
2108                         add_expression(clobbers, expr);
2109         } while (match_op(token, ','));
2110         return token;
2111 }
2112 
2113 static struct token *parse_asm_labels(struct token *token, struct statement *stmt,
2114                         struct symbol_list **labels)
2115 {
2116         struct symbol *label;
2117 
2118         do {
2119                 token = token->next; /* skip ':' and ',' */
2120                 if (token_type(token) != TOKEN_IDENT)
2121                         return token;
2122                 label = label_symbol(token);
2123                 add_symbol(labels, label);
2124                 token = token->next;
2125         } while (match_op(token, ','));
2126         return token;
2127 }
2128 
2129 static struct token *parse_asm_statement(struct token *token, struct statement *stmt)
2130 {
2131         unsigned long mods = 0;
2132 
2133         token = token->next;
2134         stmt->type = STMT_ASM;
2135         while (token_type(token) == TOKEN_IDENT) {
2136                 struct symbol *s = lookup_keyword(token->ident, NS_TYPEDEF);
2137                 if (s && s->op  && s->op->asm_modifier)
2138                         s->op->asm_modifier(token, &mods);
2139                 else if (token->ident == &goto_ident)
2140                         asm_modifier(token, &mods, MOD_ASM_GOTO);
2141                 token = token->next;
2142         }
2143         token = expect(token, '(', "after asm");
2144         token = parse_expression(token, &stmt->asm_string);
2145         if (match_op(token, ':'))
2146                 token = parse_asm_operands(token, stmt, &stmt->asm_outputs);
2147         if (match_op(token, ':'))
2148                 token = parse_asm_operands(token, stmt, &stmt->asm_inputs);
2149         if (match_op(token, ':'))
2150                 token = parse_asm_clobbers(token, stmt, &stmt->asm_clobbers);
2151         if (match_op(token, ':') && (mods & MOD_ASM_GOTO))
2152                 token = parse_asm_labels(token, stmt, &stmt->asm_labels);
2153         token = expect(token, ')', "after asm");
2154         return expect(token, ';', "at end of asm-statement");
2155 }
2156 
2157 static struct token *parse_asm_declarator(struct token *token, struct decl_state *ctx)
2158 {
2159         struct expression *expr;
2160         token = expect(token, '(', "after asm");
2161         token = parse_expression(token->next, &expr);
2162         token = expect(token, ')', "after asm");
2163         return token;
2164 }
2165 
2166 static struct token *parse_static_assert(struct token *token, struct symbol_list **unused)
2167 {
2168         struct expression *cond = NULL, *message = NULL;
2169 
2170         token = expect(token->next, '(', "after _Static_assert");
2171         token = constant_expression(token, &cond);
2172         if (!cond)
2173                 sparse_error(token->pos, "Expected constant expression");
2174         token = expect(token, ',', "after conditional expression in _Static_assert");
2175         token = parse_expression(token, &message);
2176         if (!message || message->type != EXPR_STRING) {
2177                 struct position pos;
2178 
2179                 pos = message ? message->pos : token->pos;
2180                 sparse_error(pos, "bad or missing string literal");
2181                 cond = NULL;
2182         }
2183         token = expect(token, ')', "after diagnostic message in _Static_assert");
2184 
2185         token = expect(token, ';', "after _Static_assert()");
2186 
2187         if (cond && !const_expression_value(cond) && cond->type == EXPR_VALUE)
2188                 sparse_error(cond->pos, "static assertion failed: %s",
2189                              show_string(message->string));
2190         return token;
2191 }
2192 
2193 /* Make a statement out of an expression */
2194 static struct statement *make_statement(struct expression *expr)
2195 {
2196         struct statement *stmt;
2197 
2198         if (!expr)
2199                 return NULL;
2200         stmt = alloc_statement(expr->pos, STMT_EXPRESSION);
2201         stmt->expression = expr;
2202         return stmt;
2203 }
2204 
2205 /*
2206  * All iterators have two symbols associated with them:
2207  * the "continue" and "break" symbols, which are targets
2208  * for continue and break statements respectively.
2209  *
2210  * They are in a special name-space, but they follow
2211  * all the normal visibility rules, so nested iterators
2212  * automatically work right.
2213  */
2214 static void start_iterator(struct statement *stmt)
2215 {
2216         struct symbol *cont, *brk;
2217 
2218         start_symbol_scope(stmt->pos);
2219         cont = alloc_symbol(stmt->pos, SYM_NODE);
2220         bind_symbol(cont, &continue_ident, NS_ITERATOR);
2221         brk = alloc_symbol(stmt->pos, SYM_NODE);
2222         bind_symbol(brk, &break_ident, NS_ITERATOR);
2223 
2224         stmt->type = STMT_ITERATOR;
2225         stmt->iterator_break = brk;
2226         stmt->iterator_continue = cont;
2227         fn_local_symbol(brk);
2228         fn_local_symbol(cont);
2229 }
2230 
2231 static void end_iterator(struct statement *stmt)
2232 {
2233         end_symbol_scope();
2234 }
2235 
2236 static struct statement *start_function(struct symbol *sym)
2237 {
2238         struct symbol *ret;
2239         struct statement *stmt = alloc_statement(sym->pos, STMT_COMPOUND);
2240 
2241         start_function_scope(sym->pos);
2242         ret = alloc_symbol(sym->pos, SYM_NODE);
2243         ret->ctype = sym->ctype.base_type->ctype;
2244         ret->ctype.modifiers &= ~(MOD_STORAGE | MOD_QUALIFIER | MOD_TLS | MOD_ACCESS | MOD_NOCAST | MOD_NODEREF);
2245         ret->ctype.modifiers |= (MOD_AUTO | MOD_REGISTER);
2246         bind_symbol(ret, &return_ident, NS_ITERATOR);
2247         stmt->ret = ret;
2248         fn_local_symbol(ret);
2249 
2250         // Currently parsed symbol for __func__/__FUNCTION__/__PRETTY_FUNCTION__
2251         current_fn = sym;
2252 
2253         return stmt;
2254 }
2255 
2256 static void end_function(struct symbol *sym)
2257 {
2258         current_fn = NULL;
2259         end_function_scope();
2260 }
2261 
2262 /*
2263  * A "switch()" statement, like an iterator, has a
2264  * the "break" symbol associated with it. It works
2265  * exactly like the iterator break - it's the target
2266  * for any break-statements in scope, and means that
2267  * "break" handling doesn't even need to know whether
2268  * it's breaking out of an iterator or a switch.
2269  *
2270  * In addition, the "case" symbol is a marker for the
2271  * case/default statements to find the switch statement
2272  * that they are associated with.
2273  */
2274 static void start_switch(struct statement *stmt)
2275 {
2276         struct symbol *brk, *switch_case;
2277 
2278         start_symbol_scope(stmt->pos);
2279         brk = alloc_symbol(stmt->pos, SYM_NODE);
2280         bind_symbol(brk, &break_ident, NS_ITERATOR);
2281 
2282         switch_case = alloc_symbol(stmt->pos, SYM_NODE);
2283         bind_symbol(switch_case, &case_ident, NS_ITERATOR);
2284         switch_case->stmt = stmt;
2285 
2286         stmt->type = STMT_SWITCH;
2287         stmt->switch_break = brk;
2288         stmt->switch_case = switch_case;
2289 
2290         fn_local_symbol(brk);
2291         fn_local_symbol(switch_case);
2292 }
2293 
2294 static void end_switch(struct statement *stmt)
2295 {
2296         if (!stmt->switch_case->symbol_list)
2297                 warning(stmt->pos, "switch with no cases");
2298         end_symbol_scope();
2299 }
2300 
2301 static void add_case_statement(struct statement *stmt)
2302 {
2303         struct symbol *target = lookup_symbol(&case_ident, NS_ITERATOR);
2304         struct symbol *sym;
2305 
2306         if (!target) {
2307                 sparse_error(stmt->pos, "not in switch scope");
2308                 stmt->type = STMT_NONE;
2309                 return;
2310         }
2311         sym = alloc_symbol(stmt->pos, SYM_NODE);
2312         add_symbol(&target->symbol_list, sym);
2313         sym->stmt = stmt;
2314         stmt->case_label = sym;
2315         fn_local_symbol(sym);
2316 }
2317 
2318 static struct token *parse_return_statement(struct token *token, struct statement *stmt)
2319 {
2320         struct symbol *target = lookup_symbol(&return_ident, NS_ITERATOR);
2321 
2322         if (!target)
2323                 error_die(token->pos, "internal error: return without a function target");
2324         stmt->type = STMT_RETURN;
2325         stmt->ret_target = target;
2326         return expression_statement(token->next, &stmt->ret_value);
2327 }
2328 
2329 static void validate_for_loop_decl(struct symbol *sym)
2330 {
2331         unsigned long storage = sym->ctype.modifiers & MOD_STORAGE;
2332 
2333         if (storage & ~(MOD_AUTO | MOD_REGISTER)) {
2334                 const char *name = show_ident(sym->ident);
2335                 sparse_error(sym->pos, "non-local var '%s' in for-loop initializer", name);
2336                 sym->ctype.modifiers &= ~MOD_STORAGE;
2337         }
2338 }
2339 
2340 static struct token *parse_for_statement(struct token *token, struct statement *stmt)
2341 {
2342         struct symbol_list *syms;
2343         struct expression *e1, *e2, *e3;
2344         struct statement *iterator;
2345 
2346         start_iterator(stmt);
2347         token = expect(token->next, '(', "after 'for'");
2348 
2349         syms = NULL;
2350         e1 = NULL;
2351         /* C99 variable declaration? */
2352         if (lookup_type(token)) {
2353                 token = external_declaration(token, &syms, validate_for_loop_decl);
2354         } else {
2355                 token = parse_expression(token, &e1);
2356                 token = expect(token, ';', "in 'for'");
2357         }
2358         token = parse_expression(token, &e2);
2359         token = expect(token, ';', "in 'for'");
2360         token = parse_expression(token, &e3);
2361         token = expect(token, ')', "in 'for'");
2362         token = statement(token, &iterator);
2363 
2364         stmt->iterator_syms = syms;
2365         stmt->iterator_pre_statement = make_statement(e1);
2366         stmt->iterator_pre_condition = e2;
2367         stmt->iterator_post_statement = make_statement(e3);
2368         stmt->iterator_post_condition = NULL;
2369         stmt->iterator_statement = iterator;
2370         end_iterator(stmt);
2371 
2372         return token;
2373 }
2374 
2375 static struct token *parse_while_statement(struct token *token, struct statement *stmt)
2376 {
2377         struct expression *expr;
2378         struct statement *iterator;
2379 
2380         start_iterator(stmt);
2381         token = parens_expression(token->next, &expr, "after 'while'");
2382         token = statement(token, &iterator);
2383 
2384         stmt->iterator_pre_condition = expr;
2385         stmt->iterator_post_condition = NULL;
2386         stmt->iterator_statement = iterator;
2387         end_iterator(stmt);
2388 
2389         return token;
2390 }
2391 
2392 static struct token *parse_do_statement(struct token *token, struct statement *stmt)
2393 {
2394         struct expression *expr;
2395         struct statement *iterator;
2396 
2397         start_iterator(stmt);
2398         token = statement(token->next, &iterator);
2399         if (token_type(token) == TOKEN_IDENT && token->ident == &while_ident)
2400                 token = token->next;
2401         else
2402                 sparse_error(token->pos, "expected 'while' after 'do'");
2403         token = parens_expression(token, &expr, "after 'do-while'");
2404 
2405         stmt->iterator_post_condition = expr;
2406         stmt->iterator_statement = iterator;
2407         end_iterator(stmt);
2408 
2409         if (iterator && iterator->type != STMT_COMPOUND && Wdo_while)
2410                 warning(iterator->pos, "do-while statement is not a compound statement");
2411 
2412         return expect(token, ';', "after statement");
2413 }
2414 
2415 static struct token *parse_if_statement(struct token *token, struct statement *stmt)
2416 {
2417         stmt->type = STMT_IF;
2418         token = parens_expression(token->next, &stmt->if_conditional, "after if");
2419         token = statement(token, &stmt->if_true);
2420         if (token_type(token) != TOKEN_IDENT)
2421                 return token;
2422         if (token->ident != &else_ident)
2423                 return token;
2424         return statement(token->next, &stmt->if_false);
2425 }
2426 
2427 static inline struct token *case_statement(struct token *token, struct statement *stmt)
2428 {
2429         stmt->type = STMT_CASE;
2430         token = expect(token, ':', "after default/case");
2431         add_case_statement(stmt);
2432         return statement(token, &stmt->case_statement);
2433 }
2434 
2435 static struct token *parse_case_statement(struct token *token, struct statement *stmt)
2436 {
2437         token = parse_expression(token->next, &stmt->case_expression);
2438         if (match_op(token, SPECIAL_ELLIPSIS))
2439                 token = parse_expression(token->next, &stmt->case_to);
2440         return case_statement(token, stmt);
2441 }
2442 
2443 static struct token *parse_default_statement(struct token *token, struct statement *stmt)
2444 {
2445         return case_statement(token->next, stmt);
2446 }
2447 
2448 static struct token *parse_loop_iterator(struct token *token, struct statement *stmt)
2449 {
2450         struct symbol *target = lookup_symbol(token->ident, NS_ITERATOR);
2451         stmt->type = STMT_GOTO;
2452         stmt->goto_label = target;
2453         if (!target)
2454                 sparse_error(stmt->pos, "break/continue not in iterator scope");
2455         return expect(token->next, ';', "at end of statement");
2456 }
2457 
2458 static struct token *parse_switch_statement(struct token *token, struct statement *stmt)
2459 {
2460         stmt->type = STMT_SWITCH;
2461         start_switch(stmt);
2462         token = parens_expression(token->next, &stmt->switch_expression, "after 'switch'");
2463         token = statement(token, &stmt->switch_statement);
2464         end_switch(stmt);
2465         return token;
2466 }
2467 
2468 static struct token *parse_goto_statement(struct token *token, struct statement *stmt)
2469 {
2470         stmt->type = STMT_GOTO;
2471         token = token->next;
2472         if (match_op(token, '*')) {
2473                 token = parse_expression(token->next, &stmt->goto_expression);
2474                 add_statement(&function_computed_goto_list, stmt);
2475         } else if (token_type(token) == TOKEN_IDENT) {
2476                 stmt->goto_label = label_symbol(token);
2477                 token = token->next;
2478         } else {
2479                 sparse_error(token->pos, "Expected identifier or goto expression");
2480         }
2481         return expect(token, ';', "at end of statement");
2482 }
2483 
2484 static struct token *parse_context_statement(struct token *token, struct statement *stmt)
2485 {
2486         stmt->type = STMT_CONTEXT;
2487         token = token->next;
2488         token = expect(token, '(', "after __context__ statement");
2489         token = assignment_expression(token, &stmt->expression);
2490         if (!stmt->expression)
2491                 unexpected(token, "expression expected after '('");
2492         if (match_op(token, ',')) {
2493                 token = token->next;
2494                 stmt->context = stmt->expression;
2495                 token = assignment_expression(token, &stmt->expression);
2496                 if (!stmt->expression)
2497                         unexpected(token, "expression expected after ','");
2498         }
2499         token = expect(token, ')', "at end of __context__ statement");
2500         return expect(token, ';', "at end of statement");
2501 }
2502 
2503 static struct token *parse_range_statement(struct token *token, struct statement *stmt)
2504 {
2505         stmt->type = STMT_RANGE;
2506         token = token->next;
2507         token = expect(token, '(', "after __range__ statement");
2508         token = assignment_expression(token, &stmt->range_expression);
2509         token = expect(token, ',', "after range expression");
2510         token = assignment_expression(token, &stmt->range_low);
2511         token = expect(token, ',', "after low range");
2512         token = assignment_expression(token, &stmt->range_high);
2513         token = expect(token, ')', "after range statement");
2514         return expect(token, ';', "after range statement");
2515 }
2516 
2517 static struct token *statement(struct token *token, struct statement **tree)
2518 {
2519         struct statement *stmt = alloc_statement(token->pos, STMT_NONE);
2520 
2521         *tree = stmt;
2522         if (token_type(token) == TOKEN_IDENT) {
2523                 struct symbol *s = lookup_keyword(token->ident, NS_KEYWORD);
2524                 if (s && s->op->statement)
2525                         return s->op->statement(token, stmt);
2526 
2527                 if (match_op(token->next, ':')) {
2528                         struct symbol *s = label_symbol(token);
2529                         token = skip_attributes(token->next->next);
2530                         if (s->stmt) {
2531                                 sparse_error(stmt->pos, "label '%s' redefined", show_ident(s->ident));
2532                                 // skip the label to avoid multiple definitions
2533                                 return statement(token, tree);
2534                         }
2535                         stmt->type = STMT_LABEL;
2536                         stmt->label_identifier = s;
2537                         s->stmt = stmt;
2538                         return statement(token, &stmt->label_statement);
2539                 }
2540         }
2541 
2542         if (match_op(token, '{')) {
2543                 stmt->type = STMT_COMPOUND;
2544                 start_symbol_scope(stmt->pos);
2545                 token = compound_statement(token->next, stmt);
2546                 end_symbol_scope();
2547                 
2548                 return expect(token, '}', "at end of compound statement");
2549         }
2550                         
2551         stmt->type = STMT_EXPRESSION;
2552         return expression_statement(token, &stmt->expression);
2553 }
2554 
2555 /* gcc extension - __label__ ident-list; in the beginning of compound stmt */
2556 static struct token *label_statement(struct token *token)
2557 {
2558         while (token_type(token) == TOKEN_IDENT) {
2559                 struct symbol *sym = alloc_symbol(token->pos, SYM_LABEL);
2560                 /* it's block-scope, but we want label namespace */
2561                 bind_symbol(sym, token->ident, NS_SYMBOL);
2562                 sym->namespace = NS_LABEL;
2563                 fn_local_symbol(sym);
2564                 token = token->next;
2565                 if (!match_op(token, ','))
2566                         break;
2567                 token = token->next;
2568         }
2569         return expect(token, ';', "at end of label declaration");
2570 }
2571 
2572 static struct token * statement_list(struct token *token, struct statement_list **list)
2573 {
2574         int seen_statement = 0;
2575         while (token_type(token) == TOKEN_IDENT &&
2576                token->ident == &__label___ident)
2577                 token = label_statement(token->next);
2578         for (;;) {
2579                 struct statement * stmt;
2580                 if (eof_token(token))
2581                         break;
2582                 if (match_op(token, '}'))
2583                         break;
2584                 if (match_ident(token, &_Static_assert_ident)) {
2585                         token = parse_static_assert(token, NULL);
2586                         continue;
2587                 }
2588                 if (lookup_type(token)) {
2589                         if (seen_statement) {
2590                                 warning(token->pos, "mixing declarations and code");
2591                                 seen_statement = 0;
2592                         }
2593                         stmt = alloc_statement(token->pos, STMT_DECLARATION);
2594                         token = external_declaration(token, &stmt->declaration, NULL);
2595                 } else {
2596                         seen_statement = Wdeclarationafterstatement;
2597                         token = statement(token, &stmt);
2598                 }
2599                 add_statement(list, stmt);
2600         }
2601         return token;
2602 }
2603 
2604 static struct token *identifier_list(struct token *token, struct symbol *fn)
2605 {
2606         struct symbol_list **list = &fn->arguments;
2607         for (;;) {
2608                 struct symbol *sym = alloc_symbol(token->pos, SYM_NODE);
2609                 sym->ident = token->ident;
2610                 token = token->next;
2611                 sym->endpos = token->pos;
2612                 sym->ctype.base_type = &incomplete_ctype;
2613                 add_symbol(list, sym);
2614                 if (!match_op(token, ',') ||
2615                     token_type(token->next) != TOKEN_IDENT ||
2616                     lookup_type(token->next))
2617                         break;
2618                 token = token->next;
2619         }
2620         return token;
2621 }
2622 
2623 static struct token *parameter_type_list(struct token *token, struct symbol *fn)
2624 {
2625         struct symbol_list **list = &fn->arguments;
2626 
2627         for (;;) {
2628                 struct symbol *sym;
2629 
2630                 if (match_op(token, SPECIAL_ELLIPSIS)) {
2631                         fn->variadic = 1;
2632                         token = token->next;
2633                         break;
2634                 }
2635 
2636                 sym = alloc_symbol(token->pos, SYM_NODE);
2637                 token = parameter_declaration(token, sym);
2638                 if (sym->ctype.base_type == &void_ctype) {
2639                         /* Special case: (void) */
2640                         if (!*list && !sym->ident)
2641                                 break;
2642                         warning(token->pos, "void parameter");
2643                 }
2644                 add_symbol(list, sym);
2645                 if (!match_op(token, ','))
2646                         break;
2647                 token = token->next;
2648         }
2649         return token;
2650 }
2651 
2652 struct token *compound_statement(struct token *token, struct statement *stmt)
2653 {
2654         token = statement_list(token, &stmt->stmts);
2655         return token;
2656 }
2657 
2658 static struct expression *identifier_expression(struct token *token)
2659 {
2660         struct expression *expr = alloc_expression(token->pos, EXPR_IDENTIFIER);
2661         expr->expr_ident = token->ident;
2662         return expr;
2663 }
2664 
2665 static struct expression *index_expression(struct expression *from, struct expression *to)
2666 {
2667         int idx_from, idx_to;
2668         struct expression *expr = alloc_expression(from->pos, EXPR_INDEX);
2669 
2670         idx_from = const_expression_value(from);
2671         idx_to = idx_from;
2672         if (to) {
2673                 idx_to = const_expression_value(to);
2674                 if (idx_to < idx_from || idx_from < 0)
2675                         warning(from->pos, "nonsense array initializer index range");
2676         }
2677         expr->idx_from = idx_from;
2678         expr->idx_to = idx_to;
2679         return expr;
2680 }
2681 
2682 static struct token *single_initializer(struct expression **ep, struct token *token)
2683 {
2684         int expect_equal = 0;
2685         struct token *next = token->next;
2686         struct expression **tail = ep;
2687         int nested;
2688 
2689         *ep = NULL; 
2690 
2691         if ((token_type(token) == TOKEN_IDENT) && match_op(next, ':')) {
2692                 struct expression *expr = identifier_expression(token);
2693                 if (Wold_initializer)
2694                         warning(token->pos, "obsolete struct initializer, use C99 syntax");
2695                 token = initializer(&expr->ident_expression, next->next);
2696                 if (expr->ident_expression)
2697                         *ep = expr;
2698                 return token;
2699         }
2700 
2701         for (tail = ep, nested = 0; ; nested++, next = token->next) {
2702                 if (match_op(token, '.') && (token_type(next) == TOKEN_IDENT)) {
2703                         struct expression *expr = identifier_expression(next);
2704                         *tail = expr;
2705                         tail = &expr->ident_expression;
2706                         expect_equal = 1;
2707                         token = next->next;
2708                 } else if (match_op(token, '[')) {
2709                         struct expression *from = NULL, *to = NULL, *expr;
2710                         token = constant_expression(token->next, &from);
2711                         if (!from) {
2712                                 sparse_error(token->pos, "Expected constant expression");
2713                                 break;
2714                         }
2715                         if (match_op(token, SPECIAL_ELLIPSIS))
2716                                 token = constant_expression(token->next, &to);
2717                         expr = index_expression(from, to);
2718                         *tail = expr;
2719                         tail = &expr->idx_expression;
2720                         token = expect(token, ']', "at end of initializer index");
2721                         if (nested)
2722                                 expect_equal = 1;
2723                 } else {
2724                         break;
2725                 }
2726         }
2727         if (nested && !expect_equal) {
2728                 if (!match_op(token, '='))
2729                         warning(token->pos, "obsolete array initializer, use C99 syntax");
2730                 else
2731                         expect_equal = 1;
2732         }
2733         if (expect_equal)
2734                 token = expect(token, '=', "at end of initializer index");
2735 
2736         token = initializer(tail, token);
2737         if (!*tail)
2738                 *ep = NULL;
2739         return token;
2740 }
2741 
2742 static struct token *initializer_list(struct expression_list **list, struct token *token)
2743 {
2744         struct expression *expr;
2745 
2746         for (;;) {
2747                 token = single_initializer(&expr, token);
2748                 if (!expr)
2749                         break;
2750                 add_expression(list, expr);
2751                 if (!match_op(token, ','))
2752                         break;
2753                 token = token->next;
2754         }
2755         return token;
2756 }
2757 
2758 struct token *initializer(struct expression **tree, struct token *token)
2759 {
2760         if (match_op(token, '{')) {
2761                 struct expression *expr = alloc_expression(token->pos, EXPR_INITIALIZER);
2762                 *tree = expr;
2763                 token = initializer_list(&expr->expr_list, token->next);
2764                 return expect(token, '}', "at end of initializer");
2765         }
2766         return assignment_expression(token, tree);
2767 }
2768 
2769 static void declare_argument(struct symbol *sym, struct symbol *fn)
2770 {
2771         if (!sym->ident) {
2772                 sparse_error(sym->pos, "no identifier for function argument");
2773                 return;
2774         }
2775         bind_symbol(sym, sym->ident, NS_SYMBOL);
2776 }
2777 
2778 static int is_syscall(struct symbol *sym)
2779 {
2780         char *macro;
2781         char *name;
2782         int is_syscall = 0;
2783 
2784         macro = get_macro_name(sym->pos);
2785         if (macro &&
2786             (strncmp("SYSCALL_DEFINE", macro, strlen("SYSCALL_DEFINE")) == 0 ||
2787              strncmp("COMPAT_SYSCALL_DEFINE", macro, strlen("COMPAT_SYSCALL_DEFINE")) == 0))
2788                 is_syscall = 1;
2789 
2790         name = sym->ident->name;
2791 
2792         if (name && strncmp(name, "sys_", 4) ==0)
2793                 is_syscall = 1;
2794         
2795         if (name && strncmp(name, "compat_sys_", 11) == 0)
2796                 is_syscall = 1;
2797 
2798         return is_syscall;
2799 }
2800     
2801 
2802 static struct token *parse_function_body(struct token *token, struct symbol *decl,
2803         struct symbol_list **list)
2804 {
2805         struct symbol_list **old_symbol_list;
2806         struct symbol *base_type = decl->ctype.base_type;
2807         struct statement *stmt, **p;
2808         struct symbol *prev;
2809         struct symbol *arg;
2810 
2811         old_symbol_list = function_symbol_list;
2812         if (decl->ctype.modifiers & MOD_INLINE) {
2813                 function_symbol_list = &decl->inline_symbol_list;
2814                 p = &base_type->inline_stmt;
2815         } else {
2816                 function_symbol_list = &decl->symbol_list;
2817                 p = &base_type->stmt;
2818         }
2819         function_computed_target_list = NULL;
2820         function_computed_goto_list = NULL;
2821 
2822         if ((decl->ctype.modifiers & (MOD_EXTERN|MOD_INLINE)) == MOD_EXTERN) {
2823                 if (Wexternal_function_has_definition)
2824                         warning(decl->pos, "function '%s' with external linkage has definition", show_ident(decl->ident));
2825         }
2826         if (!(decl->ctype.modifiers & MOD_STATIC))
2827                 decl->ctype.modifiers |= MOD_EXTERN;
2828 
2829         stmt = start_function(decl);
2830 
2831         *p = stmt;
2832         FOR_EACH_PTR (base_type->arguments, arg) {
2833                 declare_argument(arg, base_type);
2834         } END_FOR_EACH_PTR(arg);
2835 
2836         token = compound_statement(token->next, stmt);
2837 
2838         end_function(decl); 
2839         if (!(decl->ctype.modifiers & MOD_INLINE))
2840                 add_symbol(list, decl);
2841         else if (is_syscall(decl)) {
2842             add_symbol(list, decl);
2843             /*
2844             printf("parse.c decl: %s\n", decl->ident->name);
2845             char *macro = get_macro_name(decl->pos);
2846             printf("decl macro: %s\n", macro);
2847             */
2848         }
2849         check_declaration(decl);
2850         decl->definition = decl;
2851         prev = decl->same_symbol;
2852         if (prev && prev->definition) {
2853                 warning(decl->pos, "multiple definitions for function '%s'",
2854                         show_ident(decl->ident));
2855                 info(prev->definition->pos, " the previous one is here");
2856         } else {
2857                 while (prev) {
2858                         rebind_scope(prev, decl->scope);
2859                         prev->definition = decl;
2860                         prev = prev->same_symbol;
2861                 }
2862         }
2863         function_symbol_list = old_symbol_list;
2864         if (function_computed_goto_list) {
2865                 if (!function_computed_target_list)
2866                         warning(decl->pos, "function '%s' has computed goto but no targets?", show_ident(decl->ident));
2867                 else {
2868                         FOR_EACH_PTR(function_computed_goto_list, stmt) {
2869                                 stmt->target_list = function_computed_target_list;
2870                         } END_FOR_EACH_PTR(stmt);
2871                 }
2872         }
2873         return expect(token, '}', "at end of function");
2874 }
2875 
2876 static void promote_k_r_types(struct symbol *arg)
2877 {
2878         struct symbol *base = arg->ctype.base_type;
2879         if (base && base->ctype.base_type == &int_type && (base->ctype.modifiers & (MOD_CHAR | MOD_SHORT))) {
2880                 arg->ctype.base_type = &int_ctype;
2881         }
2882 }
2883 
2884 static void apply_k_r_types(struct symbol_list *argtypes, struct symbol *fn)
2885 {
2886         struct symbol_list *real_args = fn->ctype.base_type->arguments;
2887         struct symbol *arg;
2888 
2889         FOR_EACH_PTR(real_args, arg) {
2890                 struct symbol *type;
2891 
2892                 /* This is quadratic in the number of arguments. We _really_ don't care */
2893                 FOR_EACH_PTR(argtypes, type) {
2894                         if (type->ident == arg->ident)
2895                                 goto match;
2896                 } END_FOR_EACH_PTR(type);
2897                 if (Wimplicit_int) {
2898                         sparse_error(arg->pos, "missing type declaration for parameter '%s'",
2899                                 show_ident(arg->ident));
2900                 }
2901                 type = alloc_symbol(arg->pos, SYM_NODE);
2902                 type->ident = arg->ident;
2903                 type->ctype.base_type = &int_ctype;
2904 match:
2905                 type->used = 1;
2906                 /* "char" and "short" promote to "int" */
2907                 promote_k_r_types(type);
2908 
2909                 arg->ctype = type->ctype;
2910         } END_FOR_EACH_PTR(arg);
2911 
2912         FOR_EACH_PTR(argtypes, arg) {
2913                 if (!arg->used)
2914                         warning(arg->pos, "nonsensical parameter declaration '%s'", show_ident(arg->ident));
2915         } END_FOR_EACH_PTR(arg);
2916 
2917 }
2918 
2919 static struct token *parse_k_r_arguments(struct token *token, struct symbol *decl,
2920         struct symbol_list **list)
2921 {
2922         struct symbol_list *args = NULL;
2923 
2924         if (Wold_style_definition)
2925                 warning(token->pos, "non-ANSI definition of function '%s'", show_ident(decl->ident));
2926 
2927         do {
2928                 token = declaration_list(token, &args);
2929                 if (!match_op(token, ';')) {
2930                         sparse_error(token->pos, "expected ';' at end of parameter declaration");
2931                         break;
2932                 }
2933                 token = token->next;
2934         } while (lookup_type(token));
2935 
2936         apply_k_r_types(args, decl);
2937 
2938         if (!match_op(token, '{')) {
2939                 sparse_error(token->pos, "expected function body");
2940                 return token;
2941         }
2942         return parse_function_body(token, decl, list);
2943 }
2944 
2945 static struct token *toplevel_asm_declaration(struct token *token, struct symbol_list **list)
2946 {
2947         struct symbol *anon = alloc_symbol(token->pos, SYM_NODE);
2948         struct symbol *fn = alloc_symbol(token->pos, SYM_FN);
2949         struct statement *stmt;
2950 
2951         anon->ctype.base_type = fn;
2952         stmt = alloc_statement(token->pos, STMT_NONE);
2953         fn->stmt = stmt;
2954 
2955         token = parse_asm_statement(token, stmt);
2956 
2957         add_symbol(list, anon);
2958         return token;
2959 }
2960 
2961 struct token *external_declaration(struct token *token, struct symbol_list **list,
2962                 validate_decl_t validate_decl)
2963 {
2964         struct ident *ident = NULL;
2965         struct symbol *decl;
2966         struct decl_state ctx = { .ident = &ident };
2967         struct ctype saved;
2968         struct symbol *base_type;
2969         unsigned long mod;
2970         int is_typedef;
2971 
2972         if (match_ident(token, &_Pragma_ident))
2973                 return parse_underscore_Pragma(token);
2974 
2975         /* Top-level inline asm or static assertion? */
2976         if (token_type(token) == TOKEN_IDENT) {
2977                 struct symbol *s = lookup_keyword(token->ident, NS_KEYWORD);
2978                 if (s && s->op->toplevel)
2979                         return s->op->toplevel(token, list);
2980         }
2981 
2982         /* Parse declaration-specifiers, if any */
2983         token = declaration_specifiers(token, &ctx);
2984         mod = storage_modifiers(&ctx);
2985         mod |= ctx.ctype.modifiers & MOD_NORETURN;
2986         decl = alloc_symbol(token->pos, SYM_NODE);
2987         /* Just a type declaration? */
2988         if (match_op(token, ';')) {
2989                 apply_modifiers(token->pos, &ctx);
2990                 return token->next;
2991         }
2992 
2993         saved = ctx.ctype;
2994         token = declarator(token, &ctx);
2995         token = handle_attributes(token, &ctx, KW_ATTRIBUTE | KW_ASM);
2996         apply_modifiers(token->pos, &ctx);
2997 
2998         decl->ctype = ctx.ctype;
2999         decl->ctype.modifiers |= mod;
3000         decl->endpos = token->pos;
3001 
3002         /* Just a type declaration? */
3003         if (!ident) {
3004                 warning(token->pos, "missing identifier in declaration");
3005                 return expect(token, ';', "at the end of type declaration");
3006         }
3007 
3008         /* type define declaration? */
3009         is_typedef = ctx.storage_class == STypedef;
3010 
3011         /* Typedefs don't have meaningful storage */
3012         if (is_typedef)
3013                 decl->ctype.modifiers |= MOD_USERTYPE;
3014 
3015         bind_symbol(decl, ident, is_typedef ? NS_TYPEDEF: NS_SYMBOL);
3016 
3017         base_type = decl->ctype.base_type;
3018 
3019         if (is_typedef) {
3020                 if (base_type && !base_type->ident) {
3021                         switch (base_type->type) {
3022                         case SYM_STRUCT:
3023                         case SYM_UNION:
3024                         case SYM_ENUM:
3025                         case SYM_RESTRICT:
3026                                 base_type->ident = ident;
3027                                 break;
3028                         default:
3029                                 break;
3030                         }
3031                 }
3032         } else if (base_type && base_type->type == SYM_FN) {
3033                 if (base_type->ctype.base_type == &incomplete_ctype) {
3034                         warning(decl->pos, "'%s()' has implicit return type",
3035                                 show_ident(decl->ident));
3036                         base_type->ctype.base_type = &int_ctype;
3037                 }
3038                 /* K&R argument declaration? */
3039                 if (lookup_type(token))
3040                         return parse_k_r_arguments(token, decl, list);
3041                 if (match_op(token, '{'))
3042                         return parse_function_body(token, decl, list);
3043 
3044                 if (!(decl->ctype.modifiers & MOD_STATIC))
3045                         decl->ctype.modifiers |= MOD_EXTERN;
3046         } else if (base_type == &void_ctype && !(decl->ctype.modifiers & MOD_EXTERN)) {
3047                 sparse_error(token->pos, "void declaration");
3048         }
3049         if (base_type == &incomplete_ctype) {
3050                 warning(decl->pos, "'%s' has implicit type", show_ident(decl->ident));
3051                 decl->ctype.base_type = &int_ctype;;
3052         }
3053 
3054         for (;;) {
3055                 if (!is_typedef && match_op(token, '=')) {
3056                         token = initializer(&decl->initializer, token->next);
3057                 }
3058                 if (!is_typedef) {
3059                         if (validate_decl)
3060                                 validate_decl(decl);
3061 
3062                         if (decl->initializer && decl->ctype.modifiers & MOD_EXTERN) {
3063                                 warning(decl->pos, "symbol with external linkage has initializer");
3064                                 decl->ctype.modifiers &= ~MOD_EXTERN;
3065                         }
3066 
3067                         if (!(decl->ctype.modifiers & (MOD_EXTERN | MOD_INLINE))) {
3068                                 add_symbol(list, decl);
3069                                 fn_local_symbol(decl);
3070                         }
3071                 }
3072                 check_declaration(decl);
3073                 if (decl->same_symbol) {
3074                         decl->definition = decl->same_symbol->definition;
3075                         decl->op = decl->same_symbol->op;
3076                         if (is_typedef) {
3077                                 // TODO: handle -std=c89 --pedantic
3078                                 check_duplicates(decl);
3079                         }
3080                 }
3081 
3082                 if (!match_op(token, ','))
3083                         break;
3084 
3085                 token = token->next;
3086                 ident = NULL;
3087                 decl = alloc_symbol(token->pos, SYM_NODE);
3088                 ctx.ctype = saved;
3089                 token = handle_attributes(token, &ctx, KW_ATTRIBUTE);
3090                 token = declarator(token, &ctx);
3091                 token = handle_attributes(token, &ctx, KW_ATTRIBUTE | KW_ASM);
3092                 apply_modifiers(token->pos, &ctx);
3093                 decl->ctype = ctx.ctype;
3094                 decl->ctype.modifiers |= mod;
3095                 decl->endpos = token->pos;
3096                 if (!ident) {
3097                         sparse_error(token->pos, "expected identifier name in type definition");
3098                         return token;
3099                 }
3100 
3101                 if (is_typedef)
3102                         decl->ctype.modifiers |= MOD_USERTYPE;
3103 
3104                 bind_symbol(decl, ident, is_typedef ? NS_TYPEDEF: NS_SYMBOL);
3105 
3106                 /* Function declarations are automatically extern unless specifically static */
3107                 base_type = decl->ctype.base_type;
3108                 if (!is_typedef && base_type && base_type->type == SYM_FN) {
3109                         if (!(decl->ctype.modifiers & MOD_STATIC))
3110                                 decl->ctype.modifiers |= MOD_EXTERN;
3111                 }
3112         }
3113         return expect(token, ';', "at end of declaration");
3114 }